diff --git a/src/Game.cc b/src/Game.cc
index 69b95c2..68c2abe 100644
--- a/src/Game.cc
+++ b/src/Game.cc
@@ -14,5 +14,5 @@ gj::Game::Game(gj::Game::Param&& p) :
   param.alloc = alloc_;
   param.clock = &clock_;
   param.audio = p.audio;
-  scene_ = alloc_->MakeUniq<gj::iScene, gj::TitleScene>(param);
+  scene_ = alloc_->MakeUniq<gj::TitleScene>(param);
 }
\ No newline at end of file
diff --git a/src/GlyphElementFactory.h b/src/GlyphElementFactory.h
index 4abf8f3..aeda0de 100644
--- a/src/GlyphElementFactory.h
+++ b/src/GlyphElementFactory.h
@@ -32,7 +32,7 @@ class GlyphElementFactory : public iElementFactory {
     auto& font = FindOrCreateFont(name);
     auto  tex  = std::move(font.RenderGlyphs(ConvertStrToWstr(text), size));  /* TODO */
 
-    return alloc_->MakeUniq<iElement, TextureElement>(
+    return alloc_->MakeUniq<TextureElement>(
       param.period, std::move(tex), std::move(param.driver));
   }
 
diff --git a/src/InputWindowElementFactory.h b/src/InputWindowElementFactory.h
index 93ab970..d5a58de 100644
--- a/src/InputWindowElementFactory.h
+++ b/src/InputWindowElementFactory.h
@@ -32,10 +32,10 @@ class InputWindowElementFactory : public iElementFactory {
     p.period     = param.period;
     p.scoreboard = sb_;
     p.driver     = std::move(param.driver);
-    p.matcher    = alloc_->MakeUniq<iInputMatcher, HiraganaMatcher>(ConvertStrToWstr(kana));
+    p.matcher    = alloc_->MakeUniq<HiraganaMatcher>(ConvertStrToWstr(kana));
     p.text       = ConvertStrToWstr(text);
 
-    return alloc_->MakeUniq<iElement, InputWindowElement>(std::move(p));
+    return alloc_->MakeUniq<InputWindowElement>(std::move(p));
   }
 
  private:
diff --git a/src/LoadScene.cc b/src/LoadScene.cc
index d9b9be1..bf2009e 100644
--- a/src/LoadScene.cc
+++ b/src/LoadScene.cc
@@ -12,7 +12,7 @@ gj::LoadScene::LoadScene(Param&& p) :
 gj::UniqPtr<gj::iScene> gj::LoadScene::Update(Frame& frame) {
   if (prod_->HasPrepared() && !(orphan_ && orphan_->IsBusy())) {
     prod_->Start();
-    return UniqPtr<iScene>(prod_.release(), iAllocator::Deleter<iScene>(alloc_));
+    return std::move(prod_);
   }
 
   const uint64_t now = clock_->now();
diff --git a/src/Lua.cc b/src/Lua.cc
index dad16ab..54e2c40 100644
--- a/src/Lua.cc
+++ b/src/Lua.cc
@@ -118,7 +118,7 @@ static int CallFactory_(lua_State* L) {
 
   gj::iElementFactory::Param param;
   param.period = gj::Period(st, ed);
-  param.driver = alloc->MakeUniq<gj::iElementDriver, LuaFunc>(L, n);
+  param.driver = alloc->MakeUniq<LuaFunc>(L, n);
 
   for (int i = 3; i < n; ++i) {
     gj::iElementFactory::Param::CustomValue v;
diff --git a/src/MusicElementFactory.h b/src/MusicElementFactory.h
index 67a667e..b247f23 100644
--- a/src/MusicElementFactory.h
+++ b/src/MusicElementFactory.h
@@ -33,7 +33,7 @@ class MusicElementFactory : public iElementFactory {
     p.path   = path;
     p.offset = offset;
     p.driver = std::move(param.driver);
-    return alloc_->MakeUniq<iElement, MusicElement>(std::move(p));
+    return alloc_->MakeUniq<MusicElement>(std::move(p));
   }
 
  private:
diff --git a/src/PlayScene.cc b/src/PlayScene.cc
index ddd04c0..274e102 100644
--- a/src/PlayScene.cc
+++ b/src/PlayScene.cc
@@ -9,7 +9,7 @@
 
 gj::UniqPtr<gj::iScene> gj::PlayScene::Update(Frame& f) {
   if (store_.IsEmpty()) {
-    return param_.alloc->MakeUniq<iScene, ResultScene>(param_, sb_);
+    return param_.alloc->MakeUniq<ResultScene>(param_, sb_);
   }
 
   store_.Update(f, clock_.now());
diff --git a/src/ResultScene.cc b/src/ResultScene.cc
index fca5a6e..f44d47d 100644
--- a/src/ResultScene.cc
+++ b/src/ResultScene.cc
@@ -54,7 +54,7 @@ gj::UniqPtr<gj::iScene> gj::ResultScene::Update(Frame& f) {
   f.Add(&guide_);
 
   if (f.input.find(' ') != std::string::npos) {
-    return param_.alloc->MakeUniq<iScene, TitleScene>(param_);
+    return param_.alloc->MakeUniq<TitleScene>(param_);
   }
 
   return nullptr;
diff --git a/src/TitleScene.cc b/src/TitleScene.cc
index 4727f86..dae3bae 100644
--- a/src/TitleScene.cc
+++ b/src/TitleScene.cc
@@ -63,7 +63,7 @@ gj::UniqPtr<gj::iScene> gj::TitleScene::Update(Frame& frame) {
       param.path   = s.path;
       param.title  = s.title;
       param.orphan = std::move(music_);
-      return param_.alloc->MakeUniq<iScene, LoadScene>(std::move(param));
+      return param_.alloc->MakeUniq<LoadScene>(std::move(param));
     }
     case 'h':
       SelectScore_(select_index_? select_index_-1: list_.size()-1);
diff --git a/src/iAllocator.h b/src/iAllocator.h
index 88927c4..1c17996 100644
--- a/src/iAllocator.h
+++ b/src/iAllocator.h
@@ -19,7 +19,11 @@ public:
     Deleter& operator=(Deleter&&) = default;
     Deleter& operator=(const Deleter&) = delete;
 
-    Deleter(iAllocator* alloc) : alloc_(alloc) {
+    template <typename I>
+    Deleter(Deleter<I>&& src) {
+      alloc_ = src.alloc_;
+    }
+    explicit Deleter(iAllocator* alloc) : alloc_(alloc) {
     }
 
     void operator()(T* ptr) {
@@ -57,11 +61,6 @@ public:
     T* ptr = Alloc<T>();
     return std::unique_ptr<T, Deleter<T>>(new(ptr) T(std::forward<Args>(args)...), Deleter<T>(this));
   }
-  template <typename I, typename T, typename... Args>
-  UniqPtr<I> MakeUniq(Args&&... args) {
-    T* ptr = Alloc<T>();
-    return std::unique_ptr<I, Deleter<I>>(new(ptr) T(std::forward<Args>(args)...), Deleter<I>(this));
-  }
   template <typename T>
   UniqPtr<T> MakeUniqArray(size_t n) {
     T* ptr = Alloc<T>(n);