diff --git a/Assets/VRM10/Runtime/Components/Constraint/ConstRaintException.cs b/Assets/VRM10/Runtime/Components/Constraint/ConstRaintException.cs
new file mode 100644
index 000000000..5ec92109a
--- /dev/null
+++ b/Assets/VRM10/Runtime/Components/Constraint/ConstRaintException.cs
@@ -0,0 +1,20 @@
+using System;
+
+namespace UniVRM10
+{
+    public class ConstraintException : Exception
+    {
+        public enum ExceptionTypes
+        {
+            NoSource,
+            NoModelWithModelSpace
+        }
+
+        public readonly ExceptionTypes Type;
+
+        public ConstraintException(ExceptionTypes type)
+        {
+            Type = type;
+        }
+    }
+}
diff --git a/Assets/VRM10/Runtime/Components/Constraint/ConstRaintException.cs.meta b/Assets/VRM10/Runtime/Components/Constraint/ConstRaintException.cs.meta
new file mode 100644
index 000000000..afc5fb285
--- /dev/null
+++ b/Assets/VRM10/Runtime/Components/Constraint/ConstRaintException.cs.meta
@@ -0,0 +1,11 @@
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