diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..aa8501a
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,203 @@
+[*]
+indent_style = tab
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+indent_size = 4
+guidelines = 120
+
+[{*.meta,*.cs}]
+indent_style = space
+
+[*.meta]
+trim_trailing_whitespace = false
+indent_size = 2
+
+
+
+[*.cs]
+#### .NET コーディング規則 ####
+# https://docs.microsoft.com/visualstudio/ide/editorconfig-code-style-settings-reference
+
+### 言語規則 ###
+
+## .NET コード スタイルの設定
+
+# this. と Me. の設定
+dotnet_style_qualification_for_event = true:warning
+dotnet_style_qualification_for_field = true:warning
+dotnet_style_qualification_for_method = true:warning
+dotnet_style_qualification_for_property = true:warning
+
+# 言語キーワードと BCL の種類の設定
+dotnet_style_predefined_type_for_locals_parameters_members = true:warning
+dotnet_style_predefined_type_for_member_access = true:warning
+
+# 修飾子設定
+dotnet_style_require_accessibility_modifiers = always:warning
+csharp_preferred_modifier_order = public, private, protected, internal, static, extern, new, virtual, abstract, sealed, override, readonly, unsafe, volatile, async:warning
+
+# 式レベルの設定
+dotnet_style_prefer_inferred_tuple_names = true:warning
+dotnet_style_prefer_inferred_anonymous_type_member_names = true:warning
+dotnet_style_prefer_auto_properties = true:warning
+dotnet_style_prefer_is_null_check_over_reference_equality_method = true:warning
+
+# Null チェック設定
+dotnet_style_coalesce_expression = true:warning
+dotnet_style_null_propagation = true:warning
+
+# ドキュメント化されていないプロパティ
+# https://github.com/MicrosoftDocs/visualstudio-docs/issues/3641
+dotnet_style_operator_placement_when_wrapping = beginning_of_line
+
+## C# コード スタイルの設定
+
+# var を優先
+csharp_style_var_for_built_in_types = true:warning
+csharp_style_var_when_type_is_apparent = true:warning
+
+# 式のようなメンバー
+csharp_style_expression_bodied_properties = true:warning
+csharp_style_expression_bodied_accessors = true:warning
+
+# パターン マッチング設定
+csharp_style_pattern_matching_over_is_with_cast_check = true:warning
+csharp_style_pattern_matching_over_as_with_null_check = true:warning
+
+# インライン変数宣言
+csharp_style_inlined_variable_declaration = true:warning
+
+# 式レベルの設定
+csharp_prefer_simple_default_expression = true:warning
+
+# コード ブロックの設定
+csharp_prefer_braces = true:warning
+
+# インデックスと範囲のユーザー設定【C# 8.0】
+csharp_style_prefer_index_operator = false:error
+csharp_style_prefer_range_operator = false:error
+
+# その他のユーザー設定
+csharp_using_directive_placement = outside_namespace:warning
+# 【C# 8.0】
+csharp_style_prefer_switch_expression = false:error
+
+### 書式規則 ###
+
+## .NET 書式設定
+
+# using の整理
+dotnet_sort_system_directives_first = true
+dotnet_separate_import_directive_groups = false
+
+## C# 書式設定
+
+# 改行設定
+csharp_new_line_before_open_brace = all
+csharp_new_line_before_else = true
+csharp_new_line_before_catch = true
+csharp_new_line_before_finally = true
+csharp_new_line_before_members_in_object_initializers = true
+csharp_new_line_before_members_in_anonymous_types = true
+
+# インデント設定
+csharp_indent_case_contents = true
+csharp_indent_switch_labels = true
+csharp_indent_block_contents = true
+csharp_indent_braces = false
+csharp_indent_case_contents_when_block = false
+
+# スペース設定
+csharp_space_after_cast = false
+csharp_space_after_keywords_in_control_flow_statements = true
+csharp_space_before_colon_in_inheritance_clause = true
+csharp_space_after_colon_in_inheritance_clause = true
+csharp_space_around_binary_operators = before_and_after
+csharp_space_between_method_declaration_parameter_list_parentheses = false
+csharp_space_between_method_declaration_empty_parameter_list_parentheses = false
+csharp_space_between_method_declaration_name_and_open_parenthesis = false
+csharp_space_between_method_call_parameter_list_parentheses = false
+csharp_space_between_method_call_empty_parameter_list_parentheses = false
+csharp_space_between_method_call_name_and_opening_parenthesis = false
+csharp_space_after_comma = true
+csharp_space_before_comma = false
+csharp_space_after_dot = false
+csharp_space_before_dot = false
+csharp_space_after_semicolon_in_for_statement = true
+csharp_space_before_semicolon_in_for_statement = false
+csharp_space_around_declaration_statements = false
+csharp_space_before_open_square_brackets = false
+csharp_space_between_empty_square_brackets = false
+csharp_space_between_square_brackets = false
+
+# 折り返しの設定
+csharp_preserve_single_line_statements = false
+csharp_preserve_single_line_blocks = true
+
+### 命名規則 ###
+
+# 【camelCase】privateかつ非staticなフィールド、引数、ローカル変数
+# 【PascalCase】上記以外
+# インターフェース名には「I」を前置
+# 型パラメータ名には「T」を前置
+
+## 名前付けルール
+
+dotnet_naming_rule.private_field_should_be_camel_case.severity = warning
+dotnet_naming_rule.private_field_should_be_camel_case.symbols = private_field
+dotnet_naming_rule.private_field_should_be_camel_case.style = camel_case
+
+dotnet_naming_rule.parameter_or_local_should_be_camel_case.severity = warning
+dotnet_naming_rule.parameter_or_local_should_be_camel_case.symbols = parameter_or_local
+dotnet_naming_rule.parameter_or_local_should_be_camel_case.style = camel_case
+
+dotnet_naming_rule.others_should_be_pascal_case.severity = warning
+dotnet_naming_rule.others_should_be_pascal_case.symbols = others
+dotnet_naming_rule.others_should_be_pascal_case.style = pascal_case
+
+dotnet_naming_rule.private_static_field_should_be_camel_case.severity = warning
+dotnet_naming_rule.private_static_field_should_be_camel_case.symbols = private_static_field
+dotnet_naming_rule.private_static_field_should_be_camel_case.style = pascal_case
+
+dotnet_naming_rule.interface_should_be_prefix_i.severity = warning
+dotnet_naming_rule.interface_should_be_prefix_i.symbols = interface
+dotnet_naming_rule.interface_should_be_prefix_i.style = prefix_i
+
+dotnet_naming_rule.type_parameter_should_be_prefix_t.severity = warning
+dotnet_naming_rule.type_parameter_should_be_prefix_t.symbols = type_parameter
+dotnet_naming_rule.type_parameter_should_be_prefix_t.style = prefix_t
+
+## 記号の仕様
+
+dotnet_naming_symbols.private_field.applicable_kinds = field
+dotnet_naming_symbols.private_field.applicable_accessibilities = private
+
+dotnet_naming_symbols.parameter_or_local.applicable_kinds = parameter, local
+dotnet_naming_symbols.parameter_or_local.applicable_accessibilities = *
+
+dotnet_naming_symbols.others.applicable_kinds = *
+dotnet_naming_symbols.others.applicable_accessibilities = *
+
+dotnet_naming_symbols.private_static_field.applicable_kinds = field
+dotnet_naming_symbols.private_static_field.applicable_accessibilities = private
+dotnet_naming_symbols.private_static_field.required_modifiers = static
+
+dotnet_naming_symbols.interface.applicable_kinds = interface
+dotnet_naming_symbols.interface.applicable_accessibilities = *
+
+dotnet_naming_symbols.type_parameter.applicable_kinds = type_parameter
+dotnet_naming_symbols.type_parameter.applicable_accessibilities = *
+
+## 命名スタイル
+
+dotnet_naming_style.camel_case.capitalization = camel_case
+
+dotnet_naming_style.pascal_case.capitalization = pascal_case
+
+dotnet_naming_style.prefix_i.required_prefix = I
+dotnet_naming_style.prefix_i.capitalization = pascal_case
+
+dotnet_naming_style.prefix_t.required_prefix = T
+dotnet_naming_style.prefix_t.capitalization = pascal_case
diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..b8afbf6
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+* text=auto eol=lf encoding=utf-8
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..35ecbcb
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+# GitHubでライセンスが認識されなくなるのを防止
+/LICENSE.txt.meta
diff --git a/AssetUtility.cs b/AssetUtility.cs
new file mode 100644
index 0000000..de3c653
--- /dev/null
+++ b/AssetUtility.cs
@@ -0,0 +1,108 @@
+using System;
+using System.Linq;
+using System.Collections.Generic;
+using System.IO;
+using UnityEngine;
+using Object = UnityEngine.Object;
+using UnityEditor;
+using UniGLTF;
+using VRM;
+
+namespace Esperecyan.UniVRMExtensions
+{
+    /// <summary>
+    /// アセットの保存。
+    /// </summary>
+    internal static class AssetUtility
+    {    
+        /// <summary>
+        /// アセットの種類ごとの、複製先のフォルダ名の末尾に追加する文字列。
+        /// </summary>
+        private static readonly IDictionary<Type, string> TypeSuffixPairs = new Dictionary<Type, string>
+        {
+            { typeof(VRMMetaObject   ), ".MetaObject"  },
+            { typeof(BlendShapeAvatar), ".BlendShapes" },
+            { typeof(BlendShapeClip  ), ".BlendShapes" },
+        };
+
+        /// <summary>
+        /// プレハブアセットを生成します。
+        /// </summary>
+        /// <param name="gameObject">ヒエラルキー上のオブジェクト、またはプレハブアセット。</param>
+        /// <returns></returns>
+        internal static string CreatePrefabVariant(GameObject gameObject)
+        {
+            var path = AssetDatabase.GetAssetPath(gameObject);
+            var activeObjectIsPrefabAsset = !string.IsNullOrEmpty(path);
+            if (activeObjectIsPrefabAsset)
+            {
+                gameObject = PrefabUtility.InstantiatePrefab(gameObject) as GameObject;
+                if (Path.GetExtension(path) != ".prefab")
+                {
+                    path = $"{Path.GetDirectoryName(path)}/{Path.GetFileNameWithoutExtension(path)}.prefab";
+                }
+            }
+            else
+            {
+                path = PrefabUtility.GetNearestPrefabInstanceRoot(gameObject) == gameObject
+                    ? PrefabUtility.GetPrefabAssetPathOfNearestInstanceRoot(gameObject)
+                    : $"Assets/{gameObject.name}.prefab";
+            }
+            path = AssetDatabase.GenerateUniqueAssetPath(path);
+
+            PrefabUtility.SaveAsPrefabAsset(gameObject, path);
+            if (activeObjectIsPrefabAsset)
+            {
+                Object.DestroyImmediate(gameObject);
+            }
+
+            AssetDatabase.SaveAssets();
+
+            return path;
+        }
+
+        /// <summary>
+        /// インスタンスをプレハブが置かれているディレクトリの直下のフォルダへ保存します。
+        /// </summary>
+        /// <remarks>
+        /// 複製先にすでにアセットが存在していれば上書きし、保存先のアセットのGUIDが変わらないようにします。
+        /// </remarks>
+        /// <param name="prefabPath">「Assets/」から始まるパス。</param>
+        /// <param name="instance">保存するインスタンス。</param>
+        /// <returns></returns>
+        internal static T Save<T>(string prefabPath, T instance) where T : Object
+        {
+            var destinationPath = AssetUtility.DetermineAssetPath(prefabPath, instance);
+
+            var destination = AssetDatabase.LoadMainAssetAtPath(destinationPath);
+            if (destination)
+            {
+                EditorUtility.CopySerialized(instance, destination);
+            }
+            else
+            {
+                AssetDatabase.CreateAsset(instance, destinationPath);
+            }
+
+            return AssetDatabase.LoadAssetAtPath<T>(destinationPath);
+        }
+
+        /// <summary>
+        /// インスタンスの種類に応じて、保存先を決定します。
+        /// </summary>
+        /// <param name="prefabPath">「Assets/」から始まるパス。</param>
+        /// <param name="instance">保存するインスタンス。</param>
+        /// <returns>「Assets/」から始まるパス。</returns>
+        private static string DetermineAssetPath(string prefabPath, Object instance)
+        {
+            var destinationFolderUnityPath = UnityPath.FromUnityPath(prefabPath).GetAssetFolder(
+                AssetUtility.TypeSuffixPairs
+                    .First(typeSuffixPair => typeSuffixPair.Key.IsInstanceOfType(instance)).Value
+            );
+
+            destinationFolderUnityPath.EnsureFolder();
+
+            return destinationFolderUnityPath.Child(instance.name + ".asset").Value;
+        }
+    }
+}
diff --git a/AssetUtility.cs.meta b/AssetUtility.cs.meta
new file mode 100644
index 0000000..648fdfc
--- /dev/null
+++ b/AssetUtility.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: d050d31e7544de242970d3489f5718e8
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/Esperecyan.UniVRMExtensions.asmdef b/Esperecyan.UniVRMExtensions.asmdef
new file mode 100644
index 0000000..179642a
--- /dev/null
+++ b/Esperecyan.UniVRMExtensions.asmdef
@@ -0,0 +1,17 @@
+{
+    "name": "Esperecyan.UniVRMExtensions",
+    "references": [
+        "GUID:05dd262a0c0a2f841b8252c8c3815582"
+    ],
+    "includePlatforms": [
+        "Editor"
+    ],
+    "excludePlatforms": [],
+    "allowUnsafeCode": false,
+    "overrideReferences": false,
+    "precompiledReferences": [],
+    "autoReferenced": true,
+    "defineConstraints": [],
+    "versionDefines": [],
+    "noEngineReferences": false
+}
\ No newline at end of file
diff --git a/Esperecyan.UniVRMExtensions.asmdef.meta b/Esperecyan.UniVRMExtensions.asmdef.meta
new file mode 100644
index 0000000..2d73482
--- /dev/null
+++ b/Esperecyan.UniVRMExtensions.asmdef.meta
@@ -0,0 +1,7 @@
+fileFormatVersion: 2
+guid: ab550019837c3d44fb7a418b8b18e24a
+AssemblyDefinitionImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/LICENSE.txt b/LICENSE.txt
new file mode 100644
index 0000000..eef7c41
--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,9 @@
+MIT License
+
+© 2020 100の人
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice (including the next paragraph) shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/MenuItems.cs b/MenuItems.cs
new file mode 100644
index 0000000..47342a4
--- /dev/null
+++ b/MenuItems.cs
@@ -0,0 +1,63 @@
+using UnityEngine;
+using UnityEditor;
+using VRM;
+
+namespace Esperecyan.UniVRMExtensions
+{
+    /// <summary>
+    /// メニューアイテムへの追加とバリデート。
+    /// </summary>
+    internal static class MenuItems
+    {
+        /// <summary>
+        /// 追加するメニューアイテムの、「VRM」メニュー内の位置。
+        /// </summary>
+        private const int Priority = 1100;
+
+        [MenuItem("VRM/プレハブバリアントを作ってVRMプレハブ化", false, MenuItems.Priority)]
+        private static void Initialize()
+        {
+            var gameObject = Selection.activeObject as GameObject;
+            var animator = gameObject.GetComponent<Animator>();
+            if (animator == null || !animator.isHuman)
+            {
+                EditorUtility.DisplayDialog(
+                    VRMInitializer.Name + "-" + VRMInitializer.Version,
+                    "HumanoidのAnimatorコンポーネントがアタッチされたGameObjectを選択した状態で実行してください。",
+                    "OK"
+                );
+                return;
+            }
+
+            if (gameObject.GetComponent<VRMMeta>() != null)
+            {
+                EditorUtility.DisplayDialog(
+                    VRMInitializer.Name + "-" + VRMInitializer.Version,
+                    "選択中のアバターはVRMプレハブです。",
+                    "OK"
+                );
+                return;
+            }
+
+            var path = AssetUtility.CreatePrefabVariant(gameObject);
+
+            VRMInitializer.Initialize(path);
+
+            EditorUtility.DisplayDialog(
+                VRMInitializer.Name + "-" + VRMInitializer.Version,
+                $"「{path}」へVRMプレハブを生成しました。",
+                "OK"
+            );
+        }
+
+        /// <summary>
+        /// 選択されているオブジェクトがGameObject、かつサブアセットではなければ <c>true</c> を返します。
+        /// </summary>
+        /// <returns></returns>
+        [MenuItem("VRM/プレハブバリアントを作ってVRMプレハブ化", true)]
+        private static bool ActiveObjectIsGameObject()
+        {
+            return Selection.activeObject is GameObject gameObject && !AssetDatabase.IsSubAsset(gameObject);
+        }
+    }
+}
diff --git a/MenuItems.cs.meta b/MenuItems.cs.meta
new file mode 100644
index 0000000..dcd47e8
--- /dev/null
+++ b/MenuItems.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: c223968e8b653614a8005c7411af4f2d
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/VRMInitializer.cs b/VRMInitializer.cs
new file mode 100644
index 0000000..85ead33
--- /dev/null
+++ b/VRMInitializer.cs
@@ -0,0 +1,82 @@
+using System.Linq;
+using UnityEngine;
+using UnityEditor;
+using VRM;
+
+namespace Esperecyan.UniVRMExtensions
+{
+    /// <summary>
+    /// Hmanoidモデルを直接VRMプレハブにします。
+    /// </summary>
+    /// <remarks>
+    /// 
+    /// 
+    /// 動作確認バージョン: UniVRM 0.62.0, Unity 2020.1.16f1
+    /// ライセンス: MIT License (MIT) <https://spdx.org/licenses/MIT.html>
+    /// 配布元: <https://gist.github.com/esperecyan/>
+    /// </remarks>
+    public class VRMInitializer
+    {
+        /// <summary>
+        /// 当エディタ拡張の名称。
+        /// </summary>
+        internal const string Name = "InitializeVRM.cs";
+
+        /// <summary>
+        /// 当エディタ拡張のバージョン。
+        /// </summary>
+        internal const string Version = "1.0.0";
+
+        /// <summary>
+        /// プレハブアセットを上書きしてVRMプレハブにします。
+        /// </summary>
+        /// <param name="prefabPath">「Assets/」で始まるプレハブアセットのパス。</param>
+        public static void Initialize(string prefabPath)
+        {
+            var prefab = PrefabUtility.LoadPrefabContents(prefabPath);
+
+            var animator = prefab.GetComponent<Animator>();
+
+            var metaObject = ScriptableObject.CreateInstance<VRMMetaObject>();
+            metaObject.name = "Meta";
+            var meta = prefab.AddComponent<VRMMeta>();
+            meta.Meta = AssetUtility.Save(prefabPath, metaObject);
+
+            var humanoidDescription = prefab.AddComponent<VRMHumanoidDescription>();
+            humanoidDescription.Avatar = animator.avatar;
+
+            var blendShapeProxy = prefab.AddComponent<VRMBlendShapeProxy>();
+            var blendShapeAvatar = ScriptableObject.CreateInstance<BlendShapeAvatar>();
+            blendShapeAvatar.name = "BlendShape";
+            blendShapeProxy.BlendShapeAvatar = AssetUtility.Save(prefabPath, blendShapeAvatar);
+            blendShapeProxy.BlendShapeAvatar.CreateDefaultPreset();
+            blendShapeAvatar.Clips
+                = blendShapeAvatar.Clips.Select(clip => AssetUtility.Save(prefabPath, clip)).ToList();
+
+            var firstPerson = prefab.AddComponent<VRMFirstPerson>();
+            firstPerson.SetDefault();
+            firstPerson.TraverseRenderers();
+
+            prefab.AddComponent<VRMLookAtHead>();
+
+            var lookAtBoneApplyer = prefab.AddComponent<VRMLookAtBoneApplyer>();
+            lookAtBoneApplyer.LeftEye = OffsetOnTransform.Create(animator.GetBoneTransform(HumanBodyBones.LeftEye));
+            lookAtBoneApplyer.RightEye = OffsetOnTransform.Create(animator.GetBoneTransform(HumanBodyBones.RightEye));
+
+            var secondary = prefab.transform.Find("secondary");
+            if (secondary == null)
+            {
+                secondary = new GameObject("secondary").transform;
+                secondary.SetParent(prefab.transform, false);
+            }
+            if (secondary.GetComponent<VRMSpringBone>() == null)
+            {
+                secondary.gameObject.AddComponent<VRMSpringBone>();
+            }
+
+            PrefabUtility.SaveAsPrefabAsset(prefab, prefabPath);
+            PrefabUtility.UnloadPrefabContents(prefab);
+            AssetDatabase.SaveAssets();
+        }
+    }
+}
diff --git a/VRMInitializer.cs.meta b/VRMInitializer.cs.meta
new file mode 100644
index 0000000..56cdf87
--- /dev/null
+++ b/VRMInitializer.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: c9bf8383c03c5f444b203428f7719b78
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: