diff --git a/Assets/VRM10/Editor/Components/Constraint/VRM10RotationConstraintEditor.cs b/Assets/VRM10/Editor/Components/Constraint/VRM10RotationConstraintEditor.cs
index a09155b13..605e000a9 100644
--- a/Assets/VRM10/Editor/Components/Constraint/VRM10RotationConstraintEditor.cs
+++ b/Assets/VRM10/Editor/Components/Constraint/VRM10RotationConstraintEditor.cs
@@ -16,32 +16,11 @@ namespace UniVRM10
             m_target = (VRM10RotationConstraint)target;
         }
 
-        void DrawSrcModel()
-        {
-            var model = m_target.ModelRoot;
-            var src = m_target.Source;
-            if (model == null)
-            {
-                Handles.Label(src.position, "ModelRoot required");
-                return;
-            }
-
-            const float size = 0.05f;
-            Handles.color = Color.red;
-            Handles.DrawLine(src.position, src.position + model.right * size);
-            Handles.color = Color.green;
-            Handles.DrawLine(src.position, src.position + model.up * size);
-            Handles.color = Color.black;
-            Handles.DrawLine(src.position, src.position + model.forward * size);
-        }
-
-        void DrawSrcLocal()
+        #region SRC
+        void SrcDrawCurrent()
         {
             var s = m_target.transform.lossyScale.x;
 
-            // init 
-            Coords.Write(m_target.GetSourceLocalInit(), 0.2f / s);
-
             // current
             Handles.matrix = m_target.Source.localToWorldMatrix;
             Handles.color = Color.yellow;
@@ -49,12 +28,27 @@ namespace UniVRM10
             Handles.DrawWireCube(Vector3.zero, new Vector3(size, size, size));
         }
 
-        void DrawDstLocal()
+        void SrcDrawModelCoords()
         {
             var s = m_target.transform.lossyScale.x;
 
-            // init
-            Coords.Write(m_target.GetDstLocalInit(), 0.2f / s);
+            // init 
+            Coords.Write(m_target.GetSourceModelCoords(), 0.2f / s);
+        }
+
+        void SrcDrawLocalCoords()
+        {
+            var s = m_target.transform.lossyScale.x;
+
+            // init 
+            Coords.Write(m_target.GetSourceLocalCoords(), 0.2f / s);
+        }
+        #endregion
+
+        #region Dst
+        void DstDrawCurrent()
+        {
+            var s = m_target.transform.lossyScale.x;
 
             // current
             Handles.matrix = m_target.transform.localToWorldMatrix;
@@ -63,6 +57,20 @@ namespace UniVRM10
             Handles.DrawWireCube(Vector3.zero, new Vector3(size, size, size));
         }
 
+        void DstDrawModelCoords()
+        {
+
+        }
+
+        void DstDrawLocalCoords()
+        {
+            var s = m_target.transform.lossyScale.x;
+
+            // init
+            Coords.Write(m_target.GetDstLocalInit(), 0.2f / s);
+        }
+        #endregion
+
         static GUIStyle s_style;
 
         /// <summary>
@@ -126,29 +134,32 @@ namespace UniVRM10
             switch (m_target.SourceCoordinate)
             {
                 case ObjectSpace.model:
-                    DrawSrcModel();
+                    SrcDrawModelCoords();
                     break;
 
                 case ObjectSpace.local:
-                    DrawSrcLocal();
+                    SrcDrawLocalCoords();
                     break;
 
                 default:
                     throw new NotImplementedException();
             }
+            SrcDrawCurrent();
 
             switch (m_target.DestinationCoordinate)
             {
                 case ObjectSpace.model:
+                    DstDrawModelCoords();
                     break;
 
                 case ObjectSpace.local:
-                    DrawDstLocal();
+                    DstDrawLocalCoords();
                     break;
 
                 default:
                     throw new NotImplementedException();
             }
+            DstDrawCurrent();
         }
     }
 }
diff --git a/Assets/VRM10/Runtime/Components/Constraint/ConstraintSource.cs b/Assets/VRM10/Runtime/Components/Constraint/ConstraintSource.cs
index 43832d0a4..a3809fc75 100644
--- a/Assets/VRM10/Runtime/Components/Constraint/ConstraintSource.cs
+++ b/Assets/VRM10/Runtime/Components/Constraint/ConstraintSource.cs
@@ -8,7 +8,15 @@ namespace UniVRM10
     {
         public readonly Transform ModelRoot;
         readonly Transform m_transform;
-        readonly TRS m_modelInitial;
+
+        /// <summary>
+        /// initial: ModelRoot.localToWorldMatrix^-1 * t.localToWorldMatrix
+        /// </summary>
+        public readonly TRS ModelInitial;
+
+        /// <summary>
+        /// initial: t.localPosition, t.localRotation, t.localScale
+        /// </summary>
         public readonly TRS LocalInitial;
 
         public Vector3 TranslationDelta(ObjectSpace coords)
@@ -17,7 +25,7 @@ namespace UniVRM10
             {
                 // case ObjectSpace.World: return m_transform.position - m_initial.Translation;
                 case ObjectSpace.local: return m_transform.localPosition - LocalInitial.Translation;
-                case ObjectSpace.model: return ModelRoot.worldToLocalMatrix.MultiplyPoint(m_transform.position) - m_modelInitial.Translation;
+                case ObjectSpace.model: return ModelRoot.worldToLocalMatrix.MultiplyPoint(m_transform.position) - ModelInitial.Translation;
                 default: throw new NotImplementedException();
             }
         }
@@ -29,7 +37,7 @@ namespace UniVRM10
                 // 右からかけるか、左からかけるか、それが問題なのだ
                 // case SourceCoordinates.World: return m_transform.rotation * Quaternion.Inverse(m_initial.Rotation);
                 case ObjectSpace.local: return m_transform.localRotation * Quaternion.Inverse(LocalInitial.Rotation);
-                case ObjectSpace.model: return m_transform.rotation * Quaternion.Inverse(ModelRoot.rotation) * Quaternion.Inverse(m_modelInitial.Rotation);
+                case ObjectSpace.model: return m_transform.rotation * Quaternion.Inverse(ModelRoot.rotation) * Quaternion.Inverse(ModelInitial.Rotation);
                 default: throw new NotImplementedException();
             }
         }
@@ -45,7 +53,7 @@ namespace UniVRM10
             {
                 var world = TRS.GetWorld(t);
                 ModelRoot = modelRoot;
-                m_modelInitial = new TRS
+                ModelInitial = new TRS
                 {
                     Translation = modelRoot.worldToLocalMatrix.MultiplyPoint(world.Translation),
                     Rotation = world.Rotation * Quaternion.Inverse(ModelRoot.rotation),
diff --git a/Assets/VRM10/Runtime/Components/Constraint/VRM10RotationConstraint.cs b/Assets/VRM10/Runtime/Components/Constraint/VRM10RotationConstraint.cs
index badcdb2d7..f2e507821 100644
--- a/Assets/VRM10/Runtime/Components/Constraint/VRM10RotationConstraint.cs
+++ b/Assets/VRM10/Runtime/Components/Constraint/VRM10RotationConstraint.cs
@@ -34,25 +34,49 @@ namespace UniVRM10
         public Transform ModelRoot = default;
 
         ConstraintSource m_src;
-        public Matrix4x4 GetSourceLocalInit()
+
+        /// <summary>
+        /// Model の座標系
+        /// </summary>
+        /// <returns></returns>
+        public Matrix4x4 GetSourceModelCoords()
         {
-            if (m_src != null)
+            if (Source != null)
             {
-                var parent = Matrix4x4.identity;
-                if (Source != null && Source.parent != null)
+                if (ModelRoot != null)
                 {
-                    parent = Source.parent.localToWorldMatrix;
+                    return ModelRoot.localToWorldMatrix * Matrix4x4.Translate(Source.position);
                 }
-                return parent * m_src.LocalInitial.Matrix;
             }
-            else if (Source != null)
+
+            return Matrix4x4.identity;
+        }
+
+        /// <summary>
+        /// Local の座標系。つまり親座標系
+        /// </summary>
+        /// <returns></returns>
+        public Matrix4x4 GetSourceLocalCoords()
+        {
+            if (Source != null)
             {
-                return Source.localToWorldMatrix;
-            }
-            else
-            {
-                return Matrix4x4.identity;
+                if (m_src != null)
+                {
+                    // runtime
+                    var parent = Matrix4x4.identity;
+                    if (Source.parent != null)
+                    {
+                        parent = Source.parent.localToWorldMatrix;
+                    }
+                    return parent * m_src.LocalInitial.Matrix;
+                }
+                else
+                {
+                    return Source.localToWorldMatrix;
+                }
             }
+
+            return Matrix4x4.identity;
         }
 
         public Quaternion Delta
@@ -66,6 +90,7 @@ namespace UniVRM10
         {
             if (m_src != null)
             {
+                // runtime
                 var parent = Matrix4x4.identity;
                 if (transform.parent != null)
                 {