diff --git a/kyokusui/controller.py b/kyokusui/controller.py
index 71bca4c..59d14d0 100644
--- a/kyokusui/controller.py
+++ b/kyokusui/controller.py
@@ -1,16 +1,22 @@
 from mitama.app import Controller
 from mitama.app.http import Response
 from mitama.models import User, Node, Role, is_admin
-from datetime import datetime
 import json
 import re
 import markdown
 import magic
 
 from .model import db, Board, Thread, Res, Permission
-from .forms import CreateBoardForm, CreateThreadForm, SettingForm, UpdateThreadForm, UpdateBoardForm
+from .forms import (
+    CreateBoardForm,
+    CreateThreadForm,
+    SettingForm,
+    UpdateThreadForm,
+    UpdateBoardForm
+)
 from .utils import hiroyuki
 
+
 class HomeController(Controller):
     def handle(self, request):
         template = self.view.get_template("home.html")
@@ -24,14 +30,17 @@ def handle(self, request):
             "threads": threads,
             "boards": Board.list_subscribed(request.user)
         })
+
     def settings(self, request):
         template = self.view.get_template("settings.html")
         error = ""
         if request.method == "POST":
             form = SettingForm(request.post())
-            for permission_screen_name, permission_roles in form['permissions'].items():
-                permission = Permission.retrieve(screen_name = permission_screen_name)
-                permission.roles = [Role.retrieve(screen_name = r) for r in permission_roles]
+            for screen_name, roles in form['permissions'].items():
+                permission = Permission.retrieve(screen_name=screen_name)
+                permission.roles = [
+                    Role.retrieve(screen_name=r) for r in roles
+                ]
             permission.update()
             error = "保存しました"
         return Response.render(template, {
@@ -40,6 +49,7 @@ def settings(self, request):
             "error": error
         })
 
+
 class BoardController(Controller):
     def create(self, request):
         form = CreateBoardForm(request.post())
@@ -91,6 +101,7 @@ def unsubscribe(self, request):
             }
         })
 
+
 class UserController(Controller):
     def icon(self, request):
         user = User.retrieve(request.params['user'])
@@ -98,6 +109,7 @@ def icon(self, request):
         mime = f.from_buffer(self.icon)
         return Response(user._icon, content_type=mime)
 
+
 class ThreadController(Controller):
     def create(self, request):
         form = CreateThreadForm(request.post())
@@ -109,9 +121,12 @@ def create(self, request):
         thread.create()
         for user in board.subscribers:
             user.push({
-                "title": res.thread.title + " - Kyokusui",
+                "title": thread.title + " - Kyokusui",
                 "body": "スレッドが立ちました",
-                "icon": self.app.convert_fullurl(request, "/user/{}/icon".format(requst.user._id))
+                "icon": self.app.convert_fullurl(
+                    request,
+                    "/user/{}/icon".format(request.user._id)
+                )
             })
         return Response.json({
             "_id": thread._id,
@@ -137,8 +152,10 @@ def update(self, request):
             "title": thread.title,
         })
 
+
 class WebSocketController(Controller):
     streams = {}
+
     def handle(self, request):
         ws = request.websocket
         board = Board.retrieve(request.params['board'])
@@ -162,14 +179,22 @@ def handle(self, request):
                     res.user = request.user
                     res.thread = Thread.retrieve(request.params['thread'])
                     res.create()
-                    mentions = re.findall(r"\>\>([0-9a-zA-Z.-_]+)", data['data']['message'])
+                    mentions = re.findall(
+                        r"\>\>([0-9a-zA-Z.-_]+)",
+                        data['data']['message']
+                    )
                     for mention in mentions:
                         try:
-                            user = User.retrieve(screen_name = mention)
+                            user = User.retrieve(
+                                screen_name=mention
+                            )
                             user.push({
                                 "title": res.thread.title + " - Kyokusui",
                                 "body": res.user.name+"さんがメンションしました",
-                                "icon": self.app.convert_fullurl(request, "/user/{}/icon".format(res.user._id))
+                                "icon": self.app.convert_fullurl(
+                                    request,
+                                    "/user/{}/icon".format(res.user._id)
+                                )
                             })
                         except Exception as err:
                             print(err, mention)
@@ -181,7 +206,10 @@ def handle(self, request):
                                 "type": "message",
                                 "_id": res._id,
                                 "data": {
-                                    "message": markdown.markdown(hiroyuki(res.parsed_data["message"]), extensions=['fenced_code']),
+                                    "message": markdown.markdown(
+                                        hiroyuki(res.parsed_data["message"]),
+                                        extensions=['fenced_code']
+                                    ),
                                     "images": res.parsed_data["images"]
                                 },
                                 "user": {
@@ -189,7 +217,9 @@ def handle(self, request):
                                     "name": res.user.name,
                                     "screen_name": res.user.screen_name
                                 },
-                                "datetime": res.datetime.strftime("%Y-%m-%d %H:%M:%S"),
+                                "datetime": res.datetime.strftime(
+                                    "%Y-%m-%d %H:%M:%S"
+                                ),
                                 "thread": thread._id,
                             }))
                         except Exception as err:
diff --git a/kyokusui/model.py b/kyokusui/model.py
index 557d6d0..0a2181c 100644
--- a/kyokusui/model.py
+++ b/kyokusui/model.py
@@ -1,7 +1,7 @@
 from mitama.db import BaseDatabase, Table, relationship
 from mitama.db.model import UUID
-from mitama.db.types import *
-from mitama.models import User, Group, Node, permission
+from mitama.db.types import Column, String, ForeignKey, DateTime, Boolean, Text
+from mitama.models import User, Node, permission
 from datetime import datetime
 import json
 
@@ -12,6 +12,7 @@ class Database(BaseDatabase):
 
 db = Database(prefix="kyokusui")
 
+
 class Board(db.Model):
     name = Column(String(255))
     owner_id = Column(String(64), ForeignKey("mitama_node._id"))
@@ -24,10 +25,15 @@ def list_subscribed(cls, user):
         boards_ = cls.list()
         boards = list()
         for board in boards_:
-            if board.owner.object == user or (isinstance(board.owner.object, Group) and board.owner.object.is_in(user)) or user in board.subscribers:
+            if (
+                board.owner.object == user or
+                board.owner.is_in(user) or
+                user in board.subscribers
+            ):
                 boards.append(board)
         return boards
 
+
 class Thread(db.Model):
     board_id = Column(String(64), ForeignKey("kyokusui_board._id"))
     board = relationship(Board, backref="threads")
@@ -41,6 +47,7 @@ def close(self):
         self.closed = True
         self.update()
 
+
 class Res(db.Model):
     thread_id = Column(String(64), ForeignKey("kyokusui_thread._id"))
     thread = relationship(Thread, backref="res")
@@ -53,13 +60,24 @@ class Res(db.Model):
     def parsed_data(self):
         return json.loads(self.data)
 
-subscribe_table = Table("kyokusui_subscribe",
+
+subscribe_table = Table(
+    "kyokusui_subscribe",
     db.metadata,
     Column("_id", String(64), default=UUID(), primary_key=True),
-    Column("user_id", String(64), ForeignKey("mitama_user._id", ondelete="CASCADE")),
-    Column("board_id", String(64), ForeignKey("kyokusui_board._id", ondelete="CASCADE"))
+    Column(
+        "user_id",
+        String(64),
+        ForeignKey("mitama_user._id", ondelete="CASCADE")
+    ),
+    Column(
+        "board_id",
+        String(64),
+        ForeignKey("kyokusui_board._id", ondelete="CASCADE")
+    )
 )
 
+
 class Subscribe(db.Model):
     __table__ = subscribe_table
     user_id = subscribe_table.c.user_id,
@@ -67,6 +85,7 @@ class Subscribe(db.Model):
     user = relationship(User)
     board = relationship(Board)
 
+
 Permission = permission(db, [
     {
         "name": "板を立てる",
diff --git a/pyproject.toml b/pyproject.toml
index 6ccd88c..0907f24 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -14,7 +14,7 @@ include = [
 
 [tool.poetry.dependencies]
 python = "^3.6"
-mitama = "^4.5.8"
+mitama = "^4.5.12"
 
 [tool.poetry.dev-dependencies]
 unittest = "^0.0"