diff --git a/Editor/WorldFixedObjectProcessor.cs b/Editor/WorldFixedObjectProcessor.cs
index e022eb9e..86486943 100644
--- a/Editor/WorldFixedObjectProcessor.cs
+++ b/Editor/WorldFixedObjectProcessor.cs
@@ -87,30 +87,37 @@ namespace nadena.dev.modular_avatar.core.editor
             obj.transform.localScale = Vector3.one;
 
 #if MA_VRCSDK3_AVATARS_3_7_0_OR_NEWER
-            var constraint = obj.AddComponent(
-                System.Type.GetType("VRC.SDK3.Dynamics.Constraint.Components.VRCParentConstraint, VRC.SDK3.Dynamics.Constraint")
-            ) as VRC.Dynamics.ManagedTypes.VRCParentConstraintBase;
-            constraint.IsActive = true;
-            constraint.Locked = true;
-            constraint.AffectsPositionX = true;
-            constraint.AffectsPositionY = true;
-            constraint.AffectsPositionZ = true;
-            constraint.AffectsRotationX = true;
-            constraint.AffectsRotationY = true;
-            constraint.AffectsRotationZ = true;
-            constraint.FreezeToWorld = true;
-#else
-            var constraint = obj.AddComponent<ParentConstraint>();
-            constraint.AddSource(new ConstraintSource()
+            var isVrcAvatar = avatarRoot.TryGetComponent(out VRC.SDKBase.VRC_AvatarDescriptor _);
+
+            if (isVrcAvatar)
             {
-                weight = 1.0f,
-                sourceTransform = fixedGameObject.transform,
-            });
-            constraint.constraintActive = true;
-            constraint.locked = true;
-            constraint.rotationOffsets = new[] {Vector3.zero};
-            constraint.translationOffsets = new[] {Vector3.zero};
+                var constraint = obj.AddComponent(
+                    System.Type.GetType("VRC.SDK3.Dynamics.Constraint.Components.VRCParentConstraint, VRC.SDK3.Dynamics.Constraint")
+                ) as VRC.Dynamics.ManagedTypes.VRCParentConstraintBase;
+                constraint.IsActive = true;
+                constraint.Locked = true;
+                constraint.AffectsPositionX = true;
+                constraint.AffectsPositionY = true;
+                constraint.AffectsPositionZ = true;
+                constraint.AffectsRotationX = true;
+                constraint.AffectsRotationY = true;
+                constraint.AffectsRotationZ = true;
+                constraint.FreezeToWorld = true;
+            }
+            else
 #endif
+            {
+                var constraint = obj.AddComponent<ParentConstraint>();
+                constraint.AddSource(new ConstraintSource()
+                {
+                    weight = 1.0f,
+                    sourceTransform = fixedGameObject.transform,
+                });
+                constraint.constraintActive = true;
+                constraint.locked = true;
+                constraint.rotationOffsets = new[] {Vector3.zero};
+                constraint.translationOffsets = new[] {Vector3.zero};
+            }
 
             _proxy = obj.transform;