diff --git a/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile.ts b/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile.ts
index 6d405cf2..308bd668 100644
--- a/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile.ts
+++ b/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile.ts
@@ -1,7 +1,7 @@
 import Mastodon, { Account, Relationship, Response, Results } from 'megalodon'
 import Timeline from './AccountProfile/Timeline'
 import Follows from './AccountProfile/Follows'
-import Followers from './AccountProfile/Followers'
+import Followers, { FollowersState } from './AccountProfile/Followers'
 import { Module, MutationTree, ActionTree } from 'vuex'
 import { RootState } from '@/store'
 
@@ -11,7 +11,9 @@ export interface AccountProfileState {
   loading: boolean
 }
 
-export interface AccountProfileModuleState extends AccountProfileState {}
+export interface AccountProfileModuleState extends AccountProfileState {
+  Followers: FollowersState
+}
 
 const state = (): AccountProfileState => ({
   account: null,
diff --git a/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile/Followers.js b/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile/Followers.js
deleted file mode 100644
index 1a2152d5..00000000
--- a/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile/Followers.js
+++ /dev/null
@@ -1,46 +0,0 @@
-import Mastodon from 'megalodon'
-
-const Followers = {
-  namespaced: true,
-  state: {
-    followers: [],
-    relationships: []
-  },
-  mutations: {
-    updateFollowers (state, users) {
-      state.followers = users
-    },
-    updateRelationships (state, relations) {
-      state.relationships = relations
-    }
-  },
-  actions: {
-    fetchFollowers ({ commit, rootState }, account) {
-      const client = new Mastodon(
-        rootState.TimelineSpace.account.accessToken,
-        rootState.TimelineSpace.account.baseURL + '/api/v1'
-      )
-      return client.get(`/accounts/${account.id}/followers`, { limit: 80 })
-        .then(res => {
-          commit('updateFollowers', res.data)
-          return res.data
-        })
-    },
-    fetchRelationships ({ commit, rootState }, accounts) {
-      const ids = accounts.map(a => a.id)
-      const client = new Mastodon(
-        rootState.TimelineSpace.account.accessToken,
-        rootState.TimelineSpace.account.baseURL + '/api/v1'
-      )
-      return client.get(`/accounts/relationships`, {
-        id: ids
-      })
-        .then(res => {
-          commit('updateRelationships', res.data)
-          return res.data
-        })
-    }
-  }
-}
-
-export default Followers
diff --git a/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile/Followers.ts b/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile/Followers.ts
new file mode 100644
index 00000000..693be910
--- /dev/null
+++ b/src/renderer/store/TimelineSpace/Contents/SideBar/AccountProfile/Followers.ts
@@ -0,0 +1,60 @@
+import Mastodon, { Account, Relationship, Response } from 'megalodon'
+import { Module, MutationTree, ActionTree } from 'vuex'
+import { RootState } from '@/store'
+
+export interface FollowersState {
+  followers: Array<Account>,
+  relationships: Array<Relationship>
+}
+
+const state = (): FollowersState => ({
+  followers: [],
+  relationships: []
+})
+
+export const MUTATION_TYPES = {
+  UPDATE_FOLLOWERS: 'updateFollowers',
+  UPDATE_RELATIONSHIPS: 'updateRelationships'
+}
+
+const mutations: MutationTree<FollowersState> = {
+  [MUTATION_TYPES.UPDATE_FOLLOWERS]: (state, users: Array<Account>) => {
+    state.followers = users
+  },
+  [MUTATION_TYPES.UPDATE_RELATIONSHIPS]: (state, relations: Array<Relationship>) => {
+    state.relationships = relations
+  }
+}
+
+const actions: ActionTree<FollowersState, RootState> = {
+  fetchFollowers: async ({ commit, rootState }, account: Account) => {
+    const client = new Mastodon(
+      rootState.TimelineSpace.account.accessToken!,
+      rootState.TimelineSpace.account.baseURL + '/api/v1'
+    )
+    const res: Response<Array<Account>> = await client.get<Array<Account>>(`/accounts/${account.id}/followers`, { limit: 80 })
+    commit(MUTATION_TYPES.UPDATE_FOLLOWERS, res.data)
+    return res.data
+  },
+  fetchRelationships: async ({ commit, rootState }, accounts: Array<Account>) => {
+    const ids = accounts.map(a => a.id)
+    const client = new Mastodon(
+      rootState.TimelineSpace.account.accessToken!,
+      rootState.TimelineSpace.account.baseURL + '/api/v1'
+    )
+    const res: Response<Array<Relationship>> = await client.get<Array<Relationship>>(`/accounts/relationships`, {
+      id: ids
+    })
+    commit(MUTATION_TYPES.UPDATE_RELATIONSHIPS, res.data)
+    return res.data
+  }
+}
+
+const Followers: Module<FollowersState, RootState> = {
+  namespaced: true,
+  state: state,
+  mutations: mutations,
+  actions: actions
+}
+
+export default Followers