diff --git a/Assets/VRM10/Editor/Components/Constraint/VRM10RotationConstraintEditor.cs b/Assets/VRM10/Editor/Components/Constraint/VRM10RotationConstraintEditor.cs
index 08d430ba5..a937e80e9 100644
--- a/Assets/VRM10/Editor/Components/Constraint/VRM10RotationConstraintEditor.cs
+++ b/Assets/VRM10/Editor/Components/Constraint/VRM10RotationConstraintEditor.cs
@@ -20,12 +20,9 @@ namespace UniVRM10
         void DrawSourceCurrent()
         {
             var s = m_target.transform.lossyScale.x;
-
-            // current
-            Handles.matrix = m_target.Source.localToWorldMatrix;
+            Handles.matrix = m_target.GetSourceCurrent().TRS(0.05f * s);
             Handles.color = Color.yellow;
-            var size = 0.05f / s;
-            Handles.DrawWireCube(Vector3.zero, new Vector3(size, size, size));
+            Handles.DrawWireCube(Vector3.zero, Vector3.one);
         }
 
         void DrawSourceCoords()
diff --git a/Assets/VRM10/Runtime/Components/Constraint/ConstraintSource.cs b/Assets/VRM10/Runtime/Components/Constraint/ConstraintSource.cs
index 43d684393..0c0f3389d 100644
--- a/Assets/VRM10/Runtime/Components/Constraint/ConstraintSource.cs
+++ b/Assets/VRM10/Runtime/Components/Constraint/ConstraintSource.cs
@@ -34,10 +34,9 @@ namespace UniVRM10
         {
             switch (coords)
             {
-                // 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(ModelInitial.Rotation);
+                case ObjectSpace.model: return m_transform.rotation * Quaternion.Inverse(ModelInitial.Rotation) * Quaternion.Inverse(ModelRoot.rotation);
                 default: throw new NotImplementedException();
             }
         }
diff --git a/Assets/VRM10/Runtime/Components/Constraint/VRM10RotationConstraint.cs b/Assets/VRM10/Runtime/Components/Constraint/VRM10RotationConstraint.cs
index 14ab8a139..da13a5ea2 100644
--- a/Assets/VRM10/Runtime/Components/Constraint/VRM10RotationConstraint.cs
+++ b/Assets/VRM10/Runtime/Components/Constraint/VRM10RotationConstraint.cs
@@ -92,6 +92,61 @@ namespace UniVRM10
             throw new NotImplementedException();
         }
 
+        public TR GetSourceCurrent()
+        {
+            switch (SourceCoordinate)
+            {
+                case ObjectSpace.model:
+                    {
+                        var r = Quaternion.identity;
+                        if (Source != null)
+                        {
+                            if (ModelRoot != null)
+                            {
+                                r = ModelRoot.rotation;
+                                if (m_src != null)
+                                {
+                                    r *= m_src.RotationDelta(ObjectSpace.model);
+                                }
+                            }
+                        }
+
+                        var t = Vector3.zero;
+                        if (Source != null)
+                        {
+                            t = Source.position;
+                        }
+
+                        return new TR(r, t);
+                    }
+
+                case ObjectSpace.local:
+                    {
+                        if (Source != null)
+                        {
+                            if (m_src != null)
+                            {
+                                // runtime
+                                var parent = TR.Identity;
+                                if (Source.parent != null)
+                                {
+                                    parent = TR.FromWorld(Source.parent);
+                                }
+                                return parent * m_src.LocalInitial;
+                            }
+                            else
+                            {
+                                return TR.FromWorld(Source);
+                            }
+                        }
+
+                        return TR.Identity;
+                    }
+            }
+
+            throw new NotImplementedException();
+        }
+
         public Quaternion Delta
         {
             get;