diff --git a/Assets/VRM/Runtime/SpringBone/Jobs/Vrm0XFastSpringBoneRuntime.cs b/Assets/VRM/Runtime/SpringBone/Jobs/Vrm0XFastSpringBoneRuntime.cs
index 1a398c2a3..466976e55 100644
--- a/Assets/VRM/Runtime/SpringBone/Jobs/Vrm0XFastSpringBoneRuntime.cs
+++ b/Assets/VRM/Runtime/SpringBone/Jobs/Vrm0XFastSpringBoneRuntime.cs
@@ -22,10 +22,14 @@ namespace VRM
         SpringBoneJobs.FastSpringBoneService m_service;
         FastSpringBoneBuffer m_buffer;
 
+        public Vrm0XFastSpringboneRuntime()
+        {
+            m_service = SpringBoneJobs.FastSpringBoneService.Instance;
+        }
+
         public async Task InitializeAsync(GameObject vrm, IAwaitCaller awaitCaller)
         {
             m_vrm = vrm;
-            m_service = SpringBoneJobs.FastSpringBoneService.Instance;
 
             // default update の停止
             foreach (VRMSpringBone sb in vrm.GetComponentsInChildren<VRMSpringBone>())
diff --git a/Assets/VRM10/Runtime/Components/Vrm10Runtime/Vrm10FastSpringboneRuntime.cs b/Assets/VRM10/Runtime/Components/Vrm10Runtime/Vrm10FastSpringboneRuntime.cs
index 75793c5b1..9815287e1 100644
--- a/Assets/VRM10/Runtime/Components/Vrm10Runtime/Vrm10FastSpringboneRuntime.cs
+++ b/Assets/VRM10/Runtime/Components/Vrm10Runtime/Vrm10FastSpringboneRuntime.cs
@@ -19,6 +19,11 @@ namespace UniVRM10
         private FastSpringBones.FastSpringBoneService m_fastSpringBoneService;
         private FastSpringBoneBuffer m_fastSpringBoneBuffer;
 
+        public Vrm10FastSpringboneRuntime()
+        {
+            m_fastSpringBoneService = FastSpringBones.FastSpringBoneService.Instance;
+        }
+
         public void SetJointLevel(Transform joint, BlittableJointMutable jointSettings)
         {
             if (m_fastSpringBoneService.BufferCombiner.Combined is FastSpringBoneCombinedBuffer combined)
@@ -37,7 +42,6 @@ namespace UniVRM10
 
         public async Task InitializeAsync(Vrm10Instance instance, IAwaitCaller awaitCaller)
         {
-            m_fastSpringBoneService = FastSpringBones.FastSpringBoneService.Instance;
             m_instance = instance;
 
             // NOTE: FastSpringBoneService は UnitTest などでは動作しない