diff --git a/Assets/UniGLTF/Editor/UniGLTF/ExportDialog/GltfExportWindow.cs b/Assets/UniGLTF/Editor/UniGLTF/ExportDialog/GltfExportWindow.cs
index d567ef00a..c525a036b 100644
--- a/Assets/UniGLTF/Editor/UniGLTF/ExportDialog/GltfExportWindow.cs
+++ b/Assets/UniGLTF/Editor/UniGLTF/ExportDialog/GltfExportWindow.cs
@@ -114,16 +114,19 @@ namespace UniGLTF
             }
             else
             {
-                var (json, buffers) = data.ToGltf(path);
-                // without BOM
-                var encoding = new System.Text.UTF8Encoding(false);
-                File.WriteAllText(path, json, encoding);
-                // write to local folder
-                var dir = Path.GetDirectoryName(path);
-                foreach (var b in buffers)
+                var (json, buffer0) = data.ToGltf(path);
+
                 {
-                    var bufferPath = Path.Combine(dir, b.uri);
-                    File.WriteAllBytes(bufferPath, b.GetBytes().ToArray());
+                    // write JSON without BOM
+                    var encoding = new System.Text.UTF8Encoding(false);
+                    File.WriteAllText(path, json, encoding);
+                }
+
+                {
+                    // write to buffer0 local folder
+                    var dir = Path.GetDirectoryName(path);
+                    var bufferPath = Path.Combine(dir, buffer0.uri);
+                    File.WriteAllBytes(bufferPath, data.BinBytes.ToArray());
                 }
             }
 
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/Format/IStorage.cs b/Assets/UniGLTF/Runtime/UniGLTF/Format/IStorage.cs
index 4d4d65774..c215ccfcb 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/Format/IStorage.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/Format/IStorage.cs
@@ -12,10 +12,6 @@ namespace UniGLTF
         /// 1. url による相対パス
         /// 2. url によるbase64 encoding
         /// 3. url がnullのときに bin chunk(buffers[0]) にアクセスする
-        /// 
-        /// TODO:
-        /// 1. url による相対パス
-        /// 以外をやめて、呼び出し側で分岐させる。
         /// </summary>
         /// <param name="url"></param>
         /// <returns></returns>
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/Format/glTFBuffer.cs b/Assets/UniGLTF/Runtime/UniGLTF/Format/glTFBuffer.cs
index ed5dbb166..1721a95b8 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/Format/glTFBuffer.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/Format/glTFBuffer.cs
@@ -6,24 +6,6 @@ namespace UniGLTF
     [Serializable]
     public class glTFBuffer
     {
-        IBytesBuffer m_buffer;
-        public IBytesBuffer Buffer => m_buffer;
-
-        public void OpenStorage(IStorage storage)
-        {
-            m_buffer = new ArraySegmentByteBuffer(storage.Get(uri));
-        }
-
-        public glTFBuffer()
-        {
-
-        }
-
-        public glTFBuffer(IBytesBuffer storage)
-        {
-            m_buffer = storage;
-        }
-
         public string uri;
 
         [JsonSchema(Required = true, Minimum = 1)]
@@ -33,22 +15,6 @@ namespace UniGLTF
         public glTFExtension extensions;
         public glTFExtension extras;
         public string name;
-
-        public glTFBufferView Append<T>(T[] array, glBufferTarget target) where T : struct
-        {
-            return Append(new ArraySegment<T>(array), target);
-        }
-        public glTFBufferView Append<T>(ArraySegment<T> segment, glBufferTarget target) where T : struct
-        {
-            var view = m_buffer.Extend(segment, target);
-            byteLength = m_buffer.Bytes.Count;
-            return view;
-        }
-
-        public ArraySegment<Byte> GetBytes()
-        {
-            return m_buffer.Bytes;
-        }
     }
 
     [Serializable]
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/ExportingGltfData.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/ExportingGltfData.cs
index faed324c7..c08ee784b 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/ExportingGltfData.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/ExportingGltfData.cs
@@ -7,9 +7,13 @@ namespace UniGLTF
 {
     public class ExportingGltfData
     {
-        readonly glTF _gltf = new glTF();
+        public glTF GLTF { get; } = new glTF();
 
-        public glTF GLTF => _gltf;
+        protected IBytesBuffer _buffer;
+        /// <summary>
+        /// bin chunk
+        /// </summary>
+        public ArraySegment<byte> BinBytes => _buffer.Bytes;
 
         public ExportingGltfData(int reserved = default)
         {
@@ -17,11 +21,20 @@ namespace UniGLTF
             {
                 reserved = 50 * 1024 * 1024;
             }
-            // glb body と gltf の bin 兼用
-            _gltf.buffers.Add(new glTFBuffer(new ArrayByteBuffer(new byte[reserved])));
+
+            // buffers[0] is export target
+            GLTF.buffers.Add(new glTFBuffer());
+            _buffer = new ArrayByteBuffer(new byte[reserved]);
         }
 
         #region Buffer management for export
+        public glTFBufferView ExtendBufferAndGetView<T>(ArraySegment<T> segment, glBufferTarget target) where T : struct
+        {
+            var view = _buffer.Extend(segment, target);
+            GLTF.buffers[0].byteLength = _buffer.Bytes.Count;
+            return view;
+        }
+
         public int ExtendBufferAndGetViewIndex<T>(
             ArraySegment<T> array,
             glBufferTarget target = glBufferTarget.NONE) where T : struct
@@ -30,9 +43,9 @@ namespace UniGLTF
             {
                 return -1;
             }
-            var view = _gltf.buffers[0].Append(array, target);
-            var viewIndex = _gltf.bufferViews.Count;
-            _gltf.bufferViews.Add(view);
+            var view = ExtendBufferAndGetView(array, target);
+            var viewIndex = GLTF.bufferViews.Count;
+            GLTF.bufferViews.Add(view);
             return viewIndex;
         }
 
@@ -54,10 +67,10 @@ namespace UniGLTF
             var viewIndex = ExtendBufferAndGetViewIndex(array, target);
 
             // index buffer's byteStride is unnecessary
-            _gltf.bufferViews[viewIndex].byteStride = 0;
+            GLTF.bufferViews[viewIndex].byteStride = 0;
 
-            var accessorIndex = _gltf.accessors.Count;
-            _gltf.accessors.Add(new glTFAccessor
+            var accessorIndex = GLTF.accessors.Count;
+            GLTF.accessors.Add(new glTFAccessor
             {
                 bufferView = viewIndex,
                 byteOffset = 0,
@@ -98,8 +111,8 @@ namespace UniGLTF
                 return -1;
             }
             var sparseValuesViewIndex = ExtendBufferAndGetViewIndex(sparseValues, target);
-            var accessorIndex = _gltf.accessors.Count;
-            _gltf.accessors.Add(new glTFAccessor
+            var accessorIndex = GLTF.accessors.Count;
+            GLTF.accessors.Add(new glTFAccessor
             {
                 byteOffset = 0,
                 componentType = glTFExtensions.GetComponentType<T>(),
@@ -192,12 +205,12 @@ namespace UniGLTF
         public byte[] ToGlbBytes()
         {
             var f = new JsonFormatter();
-            GltfSerializer.Serialize(f, _gltf);
+            GltfSerializer.Serialize(f, GLTF);
 
             // remove unused extenions
             var json = f.ToString().ParseAsJson().ToString("  ");
-            RemoveUnusedExtensions(_gltf, json);
-            return Glb.Create(json, _gltf.buffers[0].GetBytes()).ToBytes();
+            RemoveUnusedExtensions(GLTF, json);
+            return Glb.Create(json, BinBytes).ToBytes();
         }
 
         /// <summary>
@@ -205,13 +218,13 @@ namespace UniGLTF
         /// </summary>
         /// <param name="gltfPath"></param>
         /// <returns></returns>
-        public (string, List<glTFBuffer>) ToGltf(string gltfPath)
+        public (string, glTFBuffer) ToGltf(string gltfPath)
         {
             // fix buffer path
-            if (_gltf.buffers.Count == 1)
+            if (GLTF.buffers.Count == 1)
             {
                 var withoutExt = Path.GetFileNameWithoutExtension(gltfPath);
-                _gltf.buffers[0].uri = $"{withoutExt}.bin";
+                GLTF.buffers[0].uri = $"{withoutExt}.bin";
             }
             else
             {
@@ -219,10 +232,10 @@ namespace UniGLTF
             }
 
             var f = new JsonFormatter();
-            GltfSerializer.Serialize(f, _gltf);
+            GltfSerializer.Serialize(f, GLTF);
             var json = f.ToString().ParseAsJson().ToString("  ");
-            RemoveUnusedExtensions(_gltf, json);
-            return (json, _gltf.buffers);
+            RemoveUnusedExtensions(GLTF, json);
+            return (json, GLTF.buffers[0]);
         }
         #endregion
     }
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/FileSystemStorage.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/FileSystemStorage.cs
index 748714d8b..285754ff9 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/FileSystemStorage.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/FileSystemStorage.cs
@@ -1,31 +1,8 @@
 using System;
-using System.Collections.Generic;
 using System.IO;
 
 namespace UniGLTF
 {
-    /// <summary>
-    /// Implement bin chunk access
-    /// </summary>
-    public class SimpleStorage : IStorage
-    {
-        ArraySegment<Byte> m_bytes;
-
-        public SimpleStorage() : this(new ArraySegment<byte>())
-        {
-        }
-
-        public SimpleStorage(ArraySegment<Byte> bytes)
-        {
-            m_bytes = bytes;
-        }
-
-        public ArraySegment<byte> Get(string url)
-        {
-            return m_bytes;
-        }
-    }
-
     /// <summary>
     /// Implement url that represnet relative path
     /// </summary>
@@ -40,30 +17,8 @@ namespace UniGLTF
 
         public ArraySegment<byte> Get(string url)
         {
-            var bytes =
-                (url.FastStartsWith("data:"))
-                ? UriByteBuffer.ReadEmbedded(url)
-                : File.ReadAllBytes(Path.Combine(m_root, url))
-                ;
+            var bytes = File.ReadAllBytes(Path.Combine(m_root, url));
             return new ArraySegment<byte>(bytes);
         }
     }
-
-    /// <summary>
-    /// for UnitTest
-    /// </summary>
-    public sealed class GltfStorage : IStorage
-    {
-        glTF _gltf;
-
-        public GltfStorage(glTF gltf)
-        {
-            _gltf = gltf;
-        }
-
-        public ArraySegment<byte> Get(string url)
-        {
-            return _gltf.buffers[0].GetBytes();
-        }
-    }
 }
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs
index 64c35f7ee..fb6107190 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs
@@ -42,18 +42,34 @@ namespace UniGLTF
         /// > This chunk MUST be the second chunk of the Binary glTF asset
         /// </summary>
         /// <returns></returns>
-        public ArraySegment<byte> Bin => Chunks[1].Bytes;
-
-        /// <summary>
-        /// URI access
-        /// </summary>
-        public IStorage _storage;
+        public ArraySegment<byte> Bin
+        {
+            get
+            {
+                if (Chunks == null)
+                {
+                    return default;
+                }
+                if (Chunks.Count < 2)
+                {
+                    return default;
+                }
+                return Chunks[1].Bytes;
+            }
+        }
 
         /// <summary>
         /// Migration Flags used by ImporterContext
         /// </summary>
         public MigrationFlags MigrationFlags { get; }
 
+        /// <summary>
+        /// URI access
+        /// </summary>
+        IStorage _storage;
+
+        Dictionary<string, ArraySegment<byte>> _dataUriCache = new Dictionary<string, ArraySegment<byte>>();
+
         public GltfData(string targetPath, string json, glTF gltf, IReadOnlyList<GlbChunk> chunks, IStorage storage, MigrationFlags migrationFlags)
         {
             TargetPath = targetPath;
@@ -64,72 +80,114 @@ namespace UniGLTF
             MigrationFlags = migrationFlags;
         }
 
-        public static GltfData CreateFromGltfDataForTest(glTF gltf, ArraySegment<byte> bytes = default)
+        public static GltfData CreateFromExportForTest(ExportingGltfData data)
+        {
+            return CreateFromGltfDataForTest(data.GLTF, data.BinBytes);
+        }
+
+        public static GltfData CreateFromGltfDataForTest(glTF gltf, ArraySegment<byte> bytes)
         {
-            IStorage storage = null;
-            if (bytes.Array != null)
-            {
-                storage = new SimpleStorage(bytes);
-            }
-            else
-            {
-                storage = new GltfStorage(gltf);
-            }
             return new GltfData(
                 string.Empty,
                 string.Empty,
                 gltf,
-                new List<GlbChunk>(),
-                storage,
+                new List<GlbChunk>
+                {
+                    new GlbChunk(), // json
+                    GlbChunk.CreateBin(bytes),
+                },
+                default,
                 new MigrationFlags()
             );
         }
 
-        public ArraySegment<Byte> GetBytes(int bufferIndex)
+        public ArraySegment<Byte> GetBytesFromUri(string uri)
         {
-            // TODO:
-            var buffer = GLTF.buffers[bufferIndex];
-            return _storage.Get(buffer.uri);
+            if (string.IsNullOrEmpty(uri))
+            {
+                throw new ArgumentNullException();
+            }
+            if (uri.StartsWith("data:", StringComparison.Ordinal))
+            {
+                if (_dataUriCache.TryGetValue(uri, out ArraySegment<byte> data))
+                {
+                    return data;
+                }
+                data = new ArraySegment<byte>(UriByteBuffer.ReadEmbedded(uri));
+                _dataUriCache.Add(uri, data);
+                return data;
+            }
+            else
+            {
+                return _storage.Get(uri);
+            }
         }
 
-        public ArraySegment<Byte> GetViewBytes(int bufferView)
+        public ArraySegment<Byte> GetBytesFromBuffer(int bufferIndex)
+        {
+            var buffer = GLTF.buffers[bufferIndex];
+            if (bufferIndex == 0 && string.IsNullOrEmpty(buffer.uri))
+            {
+                // https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#glb-stored-buffer
+                // this buffer is reference bin chunk
+                if (Bin.Array == null)
+                {
+                    throw new NullReferenceException();
+                }
+                return Bin;
+            }
+            else
+            {
+                return GetBytesFromUri(buffer.uri);
+            }
+        }
+
+        public ArraySegment<Byte> GetBytesFromBufferView(int bufferView)
         {
             var view = GLTF.bufferViews[bufferView];
-            var segment = GetBytes(view.buffer);
+            var segment = GetBytesFromBuffer(view.buffer);
             return new ArraySegment<byte>(segment.Array, segment.Offset + view.byteOffset, view.byteLength);
         }
 
-        T[] GetAttrib<T>(int count, int byteOffset, glTFBufferView view) where T : struct
+        T[] GetTypedFromBufferView<T>(int count, int byteOffset, glTFBufferView view) where T : struct
         {
-            var segment = GetBytes(view.buffer);
+            var segment = GetBytesFromBuffer(view.buffer);
             var attrib = new T[count];
             var bytes = new ArraySegment<Byte>(segment.Array, segment.Offset + view.byteOffset + byteOffset, count * view.byteStride);
             bytes.MarshalCopyTo(attrib);
             return attrib;
         }
 
-        T[] GetAttrib<T>(glTFAccessor accessor, glTFBufferView view) where T : struct
+        T[] GetTypedFromAccessor<T>(glTFAccessor accessor, glTFBufferView view) where T : struct
         {
-            return GetAttrib<T>(accessor.count, accessor.byteOffset, view);
+            return GetTypedFromBufferView<T>(accessor.count, accessor.byteOffset, view);
         }
 
-        IEnumerable<int> _GetIndices(glTFBufferView view, int count, int byteOffset, glComponentType componentType)
+        /// <summary>
+        /// for sparse
+        /// </summary>
+        /// <param name="view"></param>
+        /// <param name="count"></param>
+        /// <param name="byteOffset"></param>
+        /// <param name="componentType"></param>
+        /// <returns></returns>
+        IEnumerable<int> GetIntIndicesFromView(glTFBufferView view, int count, int byteOffset, glComponentType componentType)
         {
             switch (componentType)
             {
                 case glComponentType.UNSIGNED_BYTE:
                     {
-                        return GetAttrib<Byte>(count, byteOffset, view).Select(x => (int)(x));
+                        return GetTypedFromBufferView<Byte>(count, byteOffset, view).Select(x => (int)(x));
                     }
 
                 case glComponentType.UNSIGNED_SHORT:
                     {
-                        return GetAttrib<UInt16>(count, byteOffset, view).Select(x => (int)(x));
+                        return GetTypedFromBufferView<UInt16>(count, byteOffset, view).Select(x => (int)(x));
                     }
 
                 case glComponentType.UNSIGNED_INT:
                     {
-                        return GetAttrib<UInt32>(count, byteOffset, view).Select(x => (int)(x));
+                        return GetTypedFromBufferView<UInt32>(count, byteOffset, view).Select(x => (int)(x));
                     }
             }
             throw new NotImplementedException("GetIndices: unknown componenttype: " + componentType);
@@ -141,7 +199,7 @@ namespace UniGLTF
         /// <param name="accessor"></param>
         /// <param name="count"></param>
         /// <returns></returns>
-        IEnumerable<int> _GetIndices(glTFAccessor accessor, out int count)
+        IEnumerable<int> GetIntIndicesFromAccessor(glTFAccessor accessor, out int count)
         {
             count = accessor.count;
             var view = GLTF.bufferViews[accessor.bufferView];
@@ -149,17 +207,17 @@ namespace UniGLTF
             {
                 case glComponentType.UNSIGNED_BYTE:
                     {
-                        return GetAttrib<Byte>(accessor, view).Select(x => (int)(x));
+                        return GetTypedFromAccessor<Byte>(accessor, view).Select(x => (int)(x));
                     }
 
                 case glComponentType.UNSIGNED_SHORT:
                     {
-                        return GetAttrib<UInt16>(accessor, view).Select(x => (int)(x));
+                        return GetTypedFromAccessor<UInt16>(accessor, view).Select(x => (int)(x));
                     }
 
                 case glComponentType.UNSIGNED_INT:
                     {
-                        return GetAttrib<UInt32>(accessor, view).Select(x => (int)(x));
+                        return GetTypedFromAccessor<UInt32>(accessor, view).Select(x => (int)(x));
                     }
             }
             throw new NotImplementedException("GetIndices: unknown componenttype: " + accessor.componentType);
@@ -168,7 +226,7 @@ namespace UniGLTF
         public int[] GetIndices(int accessorIndex)
         {
             int count;
-            var result = _GetIndices(GLTF.accessors[accessorIndex], out count);
+            var result = GetIntIndicesFromAccessor(GLTF.accessors[accessorIndex], out count);
             var indices = new int[count];
 
             // flip triangles
@@ -192,7 +250,7 @@ namespace UniGLTF
             if (vertexAccessor.count <= 0) return new T[] { };
 
             var result = (vertexAccessor.bufferView != -1)
-                ? GetAttrib<T>(vertexAccessor, GLTF.bufferViews[vertexAccessor.bufferView])
+                ? GetTypedFromAccessor<T>(vertexAccessor, GLTF.bufferViews[vertexAccessor.bufferView])
                 : new T[vertexAccessor.count]
                 ;
 
@@ -200,8 +258,8 @@ namespace UniGLTF
             if (sparse != null && sparse.count > 0)
             {
                 // override sparse values
-                var indices = _GetIndices(GLTF.bufferViews[sparse.indices.bufferView], sparse.count, sparse.indices.byteOffset, sparse.indices.componentType);
-                var values = GetAttrib<T>(sparse.count, sparse.values.byteOffset, GLTF.bufferViews[sparse.values.bufferView]);
+                var indices = GetIntIndicesFromView(GLTF.bufferViews[sparse.indices.bufferView], sparse.count, sparse.indices.byteOffset, sparse.indices.componentType);
+                var values = GetTypedFromBufferView<T>(sparse.count, sparse.values.byteOffset, GLTF.bufferViews[sparse.values.bufferView]);
 
                 var it = indices.GetEnumerator();
                 for (int i = 0; i < sparse.count; ++i)
@@ -226,7 +284,7 @@ namespace UniGLTF
             {
                 var attrib = new float[vertexAccessor.count * vertexAccessor.TypeCount];
                 var view = GLTF.bufferViews[vertexAccessor.bufferView];
-                var segment = GetBytes(view.buffer);
+                var segment = GetBytesFromBuffer(view.buffer);
                 var bytes = new ArraySegment<Byte>(segment.Array, segment.Offset + view.byteOffset + vertexAccessor.byteOffset, vertexAccessor.count * view.byteStride);
                 bytes.MarshalCopyTo(attrib);
                 result = attrib;
@@ -240,8 +298,8 @@ namespace UniGLTF
             if (sparse != null && sparse.count > 0)
             {
                 // override sparse values
-                var indices = _GetIndices(GLTF.bufferViews[sparse.indices.bufferView], sparse.count, sparse.indices.byteOffset, sparse.indices.componentType);
-                var values = GetAttrib<float>(sparse.count * vertexAccessor.TypeCount, sparse.values.byteOffset, GLTF.bufferViews[sparse.values.bufferView]);
+                var indices = GetIntIndicesFromView(GLTF.bufferViews[sparse.indices.bufferView], sparse.count, sparse.indices.byteOffset, sparse.indices.componentType);
+                var values = GetTypedFromBufferView<float>(sparse.count * vertexAccessor.TypeCount, sparse.values.byteOffset, GLTF.bufferViews[sparse.values.bufferView]);
 
                 var it = indices.GetEnumerator();
                 for (int i = 0; i < sparse.count; ++i)
@@ -253,23 +311,23 @@ namespace UniGLTF
             return result;
         }
 
-        public ArraySegment<Byte> GetImageBytes(int imageIndex)
+        public ArraySegment<Byte> GetBytesFromImage(int imageIndex)
         {
             var image = GLTF.images[imageIndex];
             if (string.IsNullOrEmpty(image.uri))
             {
-                return GetViewBytes(image.bufferView);
+                return GetBytesFromBufferView(image.bufferView);
             }
             else
             {
-                return _storage.Get(image.uri);
+                return GetBytesFromUri(image.uri);
             }
         }
 
         public ArraySegment<Byte> GetImageBytesFromTextureIndex(int textureIndex)
         {
             var imageIndex = GLTF.textures[textureIndex].source;
-            return GetImageBytes(imageIndex);
+            return GetBytesFromImage(imageIndex);
         }
     }
 }
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/GlbLowLevelParser.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/GlbLowLevelParser.cs
index a0ecdfd51..bdb31f01d 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/GlbLowLevelParser.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/GlbLowLevelParser.cs
@@ -35,7 +35,7 @@ namespace UniGLTF
                     _path,
                     Encoding.UTF8.GetString(jsonBytes.Array, jsonBytes.Offset, jsonBytes.Count),
                     chunks,
-                    new SimpleStorage(chunks[1].Bytes),
+                    default,
                     new MigrationFlags()
                 );
             }
@@ -92,13 +92,6 @@ namespace UniGLTF
             FixNodeName(GLTF);
             FixAnimationNameUnique(GLTF);
 
-            // parepare byte buffer
-            //GLTF.baseDir = System.IO.Path.GetDirectoryName(Path);
-            foreach (var buffer in GLTF.buffers)
-            {
-                buffer.OpenStorage(storage);
-            }
-
             return new GltfData(path, json, GLTF, chunks, storage, migrationFlags);
         }
 
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/JsonWithStorageParser.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/JsonWithStorageParser.cs
deleted file mode 100644
index 5037dd55b..000000000
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/JsonWithStorageParser.cs
+++ /dev/null
@@ -1,32 +0,0 @@
-using System;
-using System.Collections.Generic;
-
-namespace UniGLTF
-{
-    /// <summary>
-    /// For unit tests.
-    /// JSON string with storage parser.
-    /// </summary>
-    public sealed class JsonWithStorageParser
-    {
-        private readonly string _json;
-        private readonly IStorage _storage;
-
-        public JsonWithStorageParser(string json, IStorage storage = null)
-        {
-            _json = json;
-            _storage = storage ?? new SimpleStorage(new ArraySegment<byte>());
-        }
-
-        public GltfData Parse()
-        {
-            return GlbLowLevelParser.ParseGltf(
-                string.Empty,
-                _json,
-                new List<GlbChunk>(),
-                _storage,
-                new MigrationFlags()
-            );
-        }
-    }
-}
\ No newline at end of file
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/JsonWithStorageParser.cs.meta b/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/JsonWithStorageParser.cs.meta
deleted file mode 100644
index 5437e1b24..000000000
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/Parser/JsonWithStorageParser.cs.meta
+++ /dev/null
@@ -1,3 +0,0 @@
-fileFormatVersion: 2
-guid: c103da8b4a2b4050be09e7bfce2769fd
-timeCreated: 1624803637
\ No newline at end of file
diff --git a/Assets/UniGLTF/Tests/UniGLTF/EditorTextureSerializerTests.cs b/Assets/UniGLTF/Tests/UniGLTF/EditorTextureSerializerTests.cs
index 463da1c2e..6580dbe54 100644
--- a/Assets/UniGLTF/Tests/UniGLTF/EditorTextureSerializerTests.cs
+++ b/Assets/UniGLTF/Tests/UniGLTF/EditorTextureSerializerTests.cs
@@ -143,10 +143,10 @@ namespace UniGLTF
             UnityEngine.Object.DestroyImmediate(mat);
             UnityEngine.Object.DestroyImmediate(root);
 
-            var parsed = GltfData.CreateFromGltfDataForTest(gltf);
+            var parsed = GltfData.CreateFromGltfDataForTest(gltf, data.BinBytes);
 
             // Extract Image to Texture2D
-            var exportedBytes = parsed.GetViewBytes(exportedImage.bufferView).ToArray();
+            var exportedBytes = parsed.GetBytesFromBufferView(exportedImage.bufferView).ToArray();
             var exportedTexture = new Texture2D(2, 2, TextureFormat.ARGB32, mipChain: false, linear: false);
             Assert.IsTrue(exportedTexture.LoadImage(exportedBytes)); // Always true ?
             Assert.AreEqual(srcTex.width, exportedTexture.width);
diff --git a/Assets/UniGLTF/Tests/UniGLTF/GlbParserTests.cs b/Assets/UniGLTF/Tests/UniGLTF/GlbParserTests.cs
index f8265df94..3acbc4a65 100644
--- a/Assets/UniGLTF/Tests/UniGLTF/GlbParserTests.cs
+++ b/Assets/UniGLTF/Tests/UniGLTF/GlbParserTests.cs
@@ -11,7 +11,6 @@ namespace UniGLTF
             var data = new ExportingGltfData();
             var gltf = data.GLTF;
             gltf.asset.version = "2.0";
-            gltf.buffers.Add(new glTFBuffer(new ArrayByteBuffer(Array.Empty<byte>())));
             gltf.textures.Add(new glTFTexture
             {
                 name = "FooBar",
diff --git a/Assets/UniGLTF/Tests/UniGLTF/MeshTests.cs b/Assets/UniGLTF/Tests/UniGLTF/MeshTests.cs
index 7d75ea89f..0337f0bd8 100644
--- a/Assets/UniGLTF/Tests/UniGLTF/MeshTests.cs
+++ b/Assets/UniGLTF/Tests/UniGLTF/MeshTests.cs
@@ -137,7 +137,7 @@ namespace UniGLTF
                 : MeshExporter_SharedVertexBuffer.Export(data, unityMesh, Materials, axisInverter, meshExportSettings)
                 ;
 
-            var parsed = GltfData.CreateFromGltfDataForTest(data.GLTF);
+            var parsed = GltfData.CreateFromGltfDataForTest(data.GLTF, data.BinBytes);
 
             {
                 var indices = parsed.GetIndices(gltfMesh.primitives[0].indices);
@@ -186,7 +186,7 @@ namespace UniGLTF
                 : MeshExporter_SharedVertexBuffer.Export(data, unityMesh, Materials, axisInverter, meshExportSettings)
                 ;
 
-            var parsed = GltfData.CreateFromGltfDataForTest(data.GLTF);
+            var parsed = GltfData.CreateFromGltfDataForTest(data.GLTF, data.BinBytes);
             {
                 var indices = parsed.GetIndices(gltfMesh.primitives[0].indices);
                 Assert.AreEqual(0, indices[0]);
diff --git a/Assets/UniGLTF/Tests/UniGLTF/TextureEnumerateTests.cs b/Assets/UniGLTF/Tests/UniGLTF/TextureEnumerateTests.cs
index 25765b3ef..b40ebce51 100644
--- a/Assets/UniGLTF/Tests/UniGLTF/TextureEnumerateTests.cs
+++ b/Assets/UniGLTF/Tests/UniGLTF/TextureEnumerateTests.cs
@@ -235,7 +235,7 @@ namespace UniGLTF
                 string.Empty,
                 gltf,
                 new List<GlbChunk>(),
-                new SimpleStorage(new ArraySegment<byte>()),
+                default,
                 new MigrationFlags()
             );
         }
diff --git a/Assets/UniGLTF/Tests/UniGLTF/UniGLTFTests.cs b/Assets/UniGLTF/Tests/UniGLTF/UniGLTFTests.cs
index d521af24b..0a90b7d38 100644
--- a/Assets/UniGLTF/Tests/UniGLTF/UniGLTFTests.cs
+++ b/Assets/UniGLTF/Tests/UniGLTF/UniGLTFTests.cs
@@ -115,7 +115,7 @@ namespace UniGLTF
             }
 
             // parse
-            var parsed = new JsonWithStorageParser(json).Parse();
+            var parsed = GltfData.CreateFromExportForTest(data);
 
             // import
             using (var context = new ImporterContext(parsed))
@@ -129,7 +129,8 @@ namespace UniGLTF
         {
             var initBytes = init == 0 ? null : new byte[init];
             var storage = new ArrayByteBuffer(initBytes);
-            var buffer = new glTFBuffer(storage);
+            var data = new ExportingGltfData();
+            // var buffer = new glTFBuffer(storage);
 
             var values = new List<byte>();
             int offset = 0;
@@ -139,11 +140,11 @@ namespace UniGLTF
                 values.AddRange(nums);
                 var bytes = new ArraySegment<Byte>(nums);
                 offset += x;
-                buffer.Append(bytes, glBufferTarget.NONE);
+                data.ExtendBufferAndGetView(bytes, glBufferTarget.NONE);
             }
 
-            Assert.AreEqual(values.Count, buffer.byteLength);
-            Assert.True(Enumerable.SequenceEqual(values, buffer.GetBytes().ToArray()));
+            Assert.AreEqual(values.Count, data.GLTF.buffers[0].byteLength);
+            Assert.True(Enumerable.SequenceEqual(values, data.BinBytes.ToArray()));
         }
 
         [Test]
@@ -553,9 +554,7 @@ namespace UniGLTF
 
                 // import
                 {
-                    var storage = new SimpleStorage(new ArraySegment<byte>(new byte[1024 * 1024]));
-                    var parsed = new JsonWithStorageParser(json, storage).Parse();
-
+                    var parsed = GltfData.CreateFromExportForTest(data);
                     using (var context = new ImporterContext(parsed))
                     using (var loaded = context.Load())
                     {
@@ -573,10 +572,7 @@ namespace UniGLTF
 
                 // import new version
                 {
-                    var storage = new SimpleStorage(new ArraySegment<byte>(new byte[1024 * 1024]));
-                    var parsed = new JsonWithStorageParser(json, storage).Parse();
-
-                    //Debug.LogFormat("{0}", context.Json);
+                    var parsed = GltfData.CreateFromExportForTest(data);
                     using (var context = new ImporterContext(parsed))
                     using (var loaded = context.Load())
                     {
@@ -628,9 +624,7 @@ namespace UniGLTF
 
                 // import
                 {
-                    var storage = new SimpleStorage(new ArraySegment<byte>(new byte[1024 * 1024]));
-                    var parsed = new JsonWithStorageParser(json, storage).Parse();
-
+                    var parsed = GltfData.CreateFromExportForTest(data);
                     using (var context = new ImporterContext(parsed))
                     using (var loaded = context.Load())
                     {
@@ -694,9 +688,7 @@ namespace UniGLTF
 
                 // import
                 {
-                    var storage = new SimpleStorage(new ArraySegment<byte>(new byte[1024 * 1024]));
-                    var parsed = new JsonWithStorageParser(json, storage).Parse();
-
+                    var parsed = GltfData.CreateFromExportForTest(data);
                     using (var context = new ImporterContext(parsed))
                     using (var loaded = context.Load())
                     {
diff --git a/Assets/VRM/Tests/VRMTextureEnumerateTests.cs b/Assets/VRM/Tests/VRMTextureEnumerateTests.cs
index d7fad4150..760d6106f 100644
--- a/Assets/VRM/Tests/VRMTextureEnumerateTests.cs
+++ b/Assets/VRM/Tests/VRMTextureEnumerateTests.cs
@@ -58,7 +58,8 @@ namespace VRM
                                 }
                             },
                         }
-                    }
+                    },
+                    default
                 );
                 var vrm = new glTF_VRM_extensions
                 {
@@ -119,7 +120,8 @@ namespace VRM
                             }
                         },
                     }
-                }
+                },
+                default
             );
             var vrm = new glTF_VRM_extensions
             {
diff --git a/Assets/VRM10/Runtime/IO/BufferAccessorAdapter.cs b/Assets/VRM10/Runtime/IO/BufferAccessorAdapter.cs
index 9b009aa49..d68e414fa 100644
--- a/Assets/VRM10/Runtime/IO/BufferAccessorAdapter.cs
+++ b/Assets/VRM10/Runtime/IO/BufferAccessorAdapter.cs
@@ -39,7 +39,7 @@ namespace UniVRM10
                 count = self.Count;
             }
             var slice = self.Bytes.Slice(offset * stride, count * stride);
-            return storage.AppendToBuffer(bufferIndex, slice);
+            return storage.AppendToBuffer(slice);
         }
 
         static glTFAccessor CreateGltfAccessor(this VrmLib.BufferAccessor self,
@@ -116,8 +116,8 @@ namespace UniVRM10
                         sparseValueSpan[i] = value;
                     }
 
-                    var sparseIndexView = storage.AppendToBuffer(bufferIndex, sparseIndexBin);
-                    var sparseValueView = storage.AppendToBuffer(bufferIndex, sparseValueBin);
+                    var sparseIndexView = storage.AppendToBuffer(sparseIndexBin);
+                    var sparseValueView = storage.AppendToBuffer(sparseValueBin);
 
                     var accessorIndex = storage.Gltf.accessors.Count;
                     var accessor = new glTFAccessor
diff --git a/Assets/VRM10/Runtime/IO/Texture/Vrm10TextureDescriptorGenerator.cs b/Assets/VRM10/Runtime/IO/Texture/Vrm10TextureDescriptorGenerator.cs
index ea1aaf321..c9de0bd5e 100644
--- a/Assets/VRM10/Runtime/IO/Texture/Vrm10TextureDescriptorGenerator.cs
+++ b/Assets/VRM10/Runtime/IO/Texture/Vrm10TextureDescriptorGenerator.cs
@@ -110,7 +110,7 @@ namespace UniVRM10
 
             GetTextureBytesAsync getThumbnailImageBytesAsync = () =>
             {
-                var bytes = data.GetImageBytes(imageIndex);
+                var bytes = data.GetBytesFromImage(imageIndex);
                 return Task.FromResult(GltfTextureImporter.ToArray(bytes));
             };
             var texDesc = new TextureDescriptor(objectName, gltfImage.GetExt(), gltfImage.uri, Vector2.zero, Vector2.one, default, TextureImportTypes.sRGB, default, default,
diff --git a/Assets/VRM10/Runtime/IO/Vrm10Storage.cs b/Assets/VRM10/Runtime/IO/Vrm10Storage.cs
index 3bccfbc21..c79730938 100644
--- a/Assets/VRM10/Runtime/IO/Vrm10Storage.cs
+++ b/Assets/VRM10/Runtime/IO/Vrm10Storage.cs
@@ -15,8 +15,6 @@ namespace UniVRM10
         UniGLTF.GltfData m_data;
         public UniGLTF.glTF Gltf => m_data.GLTF;
 
-        public List<UniGLTF.IBytesBuffer> Buffers;
-
         public UniGLTF.Extensions.VRMC_vrm.VRMC_vrm gltfVrm;
 
         public UniGLTF.Extensions.VRMC_springBone.VRMC_springBone gltfVrmSpringBone;
@@ -31,13 +29,9 @@ namespace UniVRM10
                 string.Empty,
                 GLTF,
                 new List<GlbChunk>(),
-                new SimpleStorage(new ArraySegment<byte>()),
+                default,
                 new MigrationFlags()
             );
-            Buffers = new List<UniGLTF.IBytesBuffer>()
-            {
-                new UniGLTF.ArrayByteBuffer()
-            };
         }
 
         /// <summary>
@@ -61,20 +55,17 @@ namespace UniVRM10
                 gltfVrmSpringBone = springBone;
             }
 
-            Buffers = new List<UniGLTF.IBytesBuffer>()
-            {
-                Gltf.buffers[0].Buffer,
-            };
+            _buffer = new ArraySegmentByteBuffer(data.Bin);
         }
 
         public void Reserve(int bytesLength)
         {
-            Buffers[0].ExtendCapacity(bytesLength);
+            _buffer.ExtendCapacity(bytesLength);
         }
 
-        public int AppendToBuffer(int bufferIndex, ArraySegment<byte> segment)
+        public int AppendToBuffer(ArraySegment<byte> segment)
         {
-            var gltfBufferView = Buffers[bufferIndex].Extend(segment);
+            var gltfBufferView = _buffer.Extend(segment);
             var viewIndex = Gltf.bufferViews.Count;
             Gltf.bufferViews.Add(gltfBufferView);
             return viewIndex;
@@ -138,7 +129,7 @@ namespace UniVRM10
                 var view = Gltf.bufferViews[bufferViewIndex];
                 if (view.buffer.TryGetValidIndex(Gltf.buffers.Count, out int bufferIndex))
                 {
-                    var buffer = Buffers[bufferIndex];
+                    var buffer = _buffer;
                     var bin = buffer.Bytes;
                     var byteSize = accessor.CalcByteSize();
                     bytes = bin.Slice(view.byteOffset, view.byteLength).Slice(accessor.byteOffset, byteSize);
@@ -480,18 +471,22 @@ namespace UniVRM10
         public ArraySegment<byte> GetBufferBytes(UniGLTF.glTFBuffer buffer)
         {
             int index = Gltf.buffers.IndexOf(buffer);
-            return Buffers[index].Bytes;
+            if (index != 0)
+            {
+                throw new NotImplementedException();
+            }
+            return _buffer.Bytes;
         }
 
         public byte[] ToBytes()
         {
-            Gltf.buffers[0].byteLength = Buffers[0].Bytes.Count;
+            Gltf.buffers[0].byteLength = _buffer.Bytes.Count;
 
             var f = new JsonFormatter();
             UniGLTF.GltfSerializer.Serialize(f, Gltf);
             var json = f.GetStoreBytes();
 
-            var glb = UniGLTF.Glb.Create(json, Buffers[0].Bytes);
+            var glb = UniGLTF.Glb.Create(json, _buffer.Bytes);
             return glb.ToBytes();
         }
     }
diff --git a/Assets/VRM10/Runtime/Migration/MeshUpdater.cs b/Assets/VRM10/Runtime/Migration/MeshUpdater.cs
index aac291e6d..24e3dda1f 100644
--- a/Assets/VRM10/Runtime/Migration/MeshUpdater.cs
+++ b/Assets/VRM10/Runtime/Migration/MeshUpdater.cs
@@ -69,7 +69,7 @@ namespace UniVRM10
             // copy images
             foreach (var image in gltf.images)
             {
-                var bytes = _data.GetViewBytes(image.bufferView);
+                var bytes = _data.GetBytesFromBufferView(image.bufferView);
                 image.bufferView = AddBuffer(bytes);
             }
 
diff --git a/Assets/VRM10/Runtime/Migration/RotateY180.cs b/Assets/VRM10/Runtime/Migration/RotateY180.cs
index fb7ca77c2..4ada62c1c 100644
--- a/Assets/VRM10/Runtime/Migration/RotateY180.cs
+++ b/Assets/VRM10/Runtime/Migration/RotateY180.cs
@@ -72,7 +72,7 @@ namespace UniVRM10
 
             if (bufferViewIndex != -1)
             {
-                var buffer = data.GetViewBytes(bufferViewIndex);
+                var buffer = data.GetBytesFromBufferView(bufferViewIndex);
                 var span = SpanLike.Wrap<UnityEngine.Vector3>(buffer);
                 for (int i = 0; i < span.Length; ++i)
                 {
@@ -113,7 +113,7 @@ namespace UniVRM10
                 if (used.Add(skin.inverseBindMatrices))
                 {
                     var accessor = data.GLTF.accessors[skin.inverseBindMatrices];
-                    var buffer = data.GetViewBytes(accessor.bufferView);
+                    var buffer = data.GetBytesFromBufferView(accessor.bufferView);
                     var span = SpanLike.Wrap<UnityEngine.Matrix4x4>(buffer);
                     for (int i = 0; i < span.Length; ++i)
                     {