diff --git a/src/lang/en.ts b/src/lang/en.ts
index 2b79c11c..02f23194 100644
--- a/src/lang/en.ts
+++ b/src/lang/en.ts
@@ -708,4 +708,10 @@ export const languageEnglish = {
     customCSS: "Custom CSS",
     betaMobileGUI: "Beta Mobile GUI",
     menu: "Menu",
+    connectionOpen: "Connection Open",
+    connectionOpenInfo: "Multiuser room is opened. you can share the room code to other users. others can join the room by using the code inside playground > Join Multiuser Room.",
+    createMultiuserRoom: "Create Multiuser Room",
+    connectionHost: "You are the host of the room.",
+    connectionGuest: "You are the guest of the room.",
+    otherUserRequesting: "Other user is already requesting. try again later.",
 }
\ No newline at end of file
diff --git a/src/lib/ChatScreens/Chat.svelte b/src/lib/ChatScreens/Chat.svelte
index 03e3b18f..72d8da0b 100644
--- a/src/lib/ChatScreens/Chat.svelte
+++ b/src/lib/ChatScreens/Chat.svelte
@@ -15,6 +15,7 @@
     import { capitalize } from "src/ts/util";
   import { longpress } from "src/ts/gui/longtouch";
   import { ColorSchemeTypeStore } from "src/ts/gui/colorscheme";
+  import { ConnectionOpenStore } from "src/ts/sync/multiuser";
     export let message = ''
     export let name = ''
     export let largePortrait = false
@@ -202,20 +203,22 @@
                             </button>
                         {/if}
 
-                        <button class={"ml-2 hover:text-green-500 transition-colors "+(editMode?'text-green-400':'')} on:click={() => {
-                            if(!editMode){
-                                editMode = true
-                            }
-                            else{
-                                editMode = false
-                                edit()
-                            }
-                        }}>
-                            <PencilIcon size={20}/>
-                        </button>
-                        <button class="ml-2 hover:text-green-500 transition-colors" on:click={(e) => rm(e, false)} use:longpress={(e) => rm(e, true)}>
-                            <TrashIcon size={20}/>
-                        </button>
+                        {#if !$ConnectionOpenStore}
+                            <button class={"ml-2 hover:text-green-500 transition-colors "+(editMode?'text-green-400':'')} on:click={() => {
+                                if(!editMode){
+                                    editMode = true
+                                }
+                                else{
+                                    editMode = false
+                                    edit()
+                                }
+                            }}>
+                                <PencilIcon size={20}/>
+                            </button>
+                            <button class="ml-2 hover:text-green-500 transition-colors" on:click={(e) => rm(e, false)} use:longpress={(e) => rm(e, true)}>
+                                <TrashIcon size={20}/>
+                            </button>
+                        {/if}
                     {/if}
                     {#if $DataBase.translator !== '' && !blankMessage}
                         <button class={"ml-2 cursor-pointer hover:text-green-500 transition-colors " + (translated ? 'text-green-400':'')} class:translating={translating} on:click={async () => {
diff --git a/src/lib/ChatScreens/DefaultChatScreen.svelte b/src/lib/ChatScreens/DefaultChatScreen.svelte
index b006f717..9ca3379e 100644
--- a/src/lib/ChatScreens/DefaultChatScreen.svelte
+++ b/src/lib/ChatScreens/DefaultChatScreen.svelte
@@ -25,6 +25,7 @@
     import { postChatFile } from 'src/ts/process/files/multisend';
     import { getInlayImage } from 'src/ts/process/files/image';
     import PlaygroundMenu from '../Playground/PlaygroundMenu.svelte';
+  import { ConnectionOpenStore } from 'src/ts/sync/multiuser';
 
     let messageInput:string = ''
     let messageInputTranslate:string = ''
@@ -81,7 +82,8 @@
                     if($DataBase.useSayNothing){
                         cha.push({
                             role: 'user',
-                            data: '*says nothing*'
+                            data: '*says nothing*',
+                            name: $ConnectionOpenStore ? $CurrentUsername : null
                         })
                     }
                 }
@@ -98,14 +100,16 @@
                 cha.push({
                     role: 'user',
                     data: await processScript(char,messageInput,'editinput'),
-                    time: Date.now()
+                    time: Date.now(),
+                    name: $ConnectionOpenStore ? $CurrentUsername : null
                 })
             }
             else{
                 cha.push({
                     role: 'user',
                     data: messageInput,
-                    time: Date.now()
+                    time: Date.now(),
+                    name: $ConnectionOpenStore ? $CurrentUsername : null
                 })
             }
         }
@@ -583,9 +587,9 @@
                     <Chat
                         character={$CurrentSimpleCharacter}
                         idx={chat.index}
-                        name={$CurrentUsername} 
+                        name={chat.name ?? $CurrentUsername} 
                         message={chat.data}
-                        img={getCharImage($CurrentUserIcon, 'css')}
+                        img={$ConnectionOpenStore ? '' : getCharImage($CurrentUserIcon, 'css')}
                         isLastMemory={$CurrentChat.lastMemory === (chat.chatId ?? 'none') && $CurrentShowMemoryLimit}
                         largePortrait={$UserIconProtrait}
                         MessageGenerationInfo={chat.generationInfo}
diff --git a/src/lib/Others/AlertComp.svelte b/src/lib/Others/AlertComp.svelte
index a3742264..3274d1eb 100644
--- a/src/lib/Others/AlertComp.svelte
+++ b/src/lib/Others/AlertComp.svelte
@@ -19,6 +19,7 @@
     import TextAreaInput from "../UI/GUI/TextAreaInput.svelte";
     import ModuleChatMenu from "../Setting/Pages/Module/ModuleChatMenu.svelte";
   import { ColorSchemeTypeStore } from "src/ts/gui/colorscheme";
+  import Help from "./Help.svelte";
     let btn
     let input = ''
     let cardExportType = 'realm'
@@ -399,6 +400,21 @@
                             <ChevronRightIcon />
                         </div>
                     </button>
+                    {#if $DataBase.useExperimental}
+                        <button class="border-darkborderc border py-2 px-8 flex rounded-md hover:ring-2 items-center mt-2" on:click={() => {
+                            alertStore.set({
+                                type: 'none',
+                                msg: '2'
+                            })
+                        }}>
+                            <div class="flex flex-col justify-start items-start">
+                                <span>{language.createMultiuserRoom} <Help key="experimental"/></span>
+                            </div>
+                            <div class="ml-9 float-right flex-1 flex justify-end">
+                                <ChevronRightIcon />
+                            </div>
+                        </button>
+                    {/if}
                     <button class="border-darkborderc border py-2 px-8 flex rounded-md hover:ring-2 items-center mt-2" on:click={() => {
                         alertStore.set({
                             type: 'none',
diff --git a/src/lib/Playground/PlaygroundMenu.svelte b/src/lib/Playground/PlaygroundMenu.svelte
index 9359c1fb..9ddffd10 100644
--- a/src/lib/Playground/PlaygroundMenu.svelte
+++ b/src/lib/Playground/PlaygroundMenu.svelte
@@ -13,6 +13,7 @@
     import PlaygroundImageGen from "./PlaygroundImageGen.svelte";
     import PlaygroundParser from "./PlaygroundParser.svelte";
     import ToolConvertion from "./ToolConvertion.svelte";
+  import { joinMultiuserRoom } from "src/ts/sync/multiuser";
 
     let easterEggTouch = 0
 
@@ -89,6 +90,11 @@
             }}>
                 <h1 class="text-2xl font-bold text-start">{language.promptConvertion}</h1>
             </button>
+            <button class="bg-darkbg rounded-md p-6 flex flex-col transition-shadow hover:ring-1" on:click={() => {
+                joinMultiuserRoom()
+            }}>
+                <h1 class="text-2xl font-bold text-start">{language.joinMultiUserRoom}</h1>
+            </button>
             <button class="bg-darkbg rounded-md p-6 flex flex-col transition-shadow hover:ring-1" on:click={() => {
                 easterEggTouch += 1
             }}>
diff --git a/src/lib/SideBars/SideChatList.svelte b/src/lib/SideBars/SideChatList.svelte
index fde445ed..0f230e4b 100644
--- a/src/lib/SideBars/SideChatList.svelte
+++ b/src/lib/SideBars/SideChatList.svelte
@@ -127,6 +127,10 @@
                                 }
                             }
                         }
+                        case 2:{
+                            chara.chatPage = i
+                            createMultiuserRoom()
+                        }
                     }
                 }}>
                     <MenuIcon size={18}/>
diff --git a/src/lib/SideBars/Sidebar.svelte b/src/lib/SideBars/Sidebar.svelte
index f17548a2..63b2efab 100644
--- a/src/lib/SideBars/Sidebar.svelte
+++ b/src/lib/SideBars/Sidebar.svelte
@@ -51,7 +51,7 @@
     import Button from "../UI/GUI/Button.svelte";
     import { alertAddCharacter, alertInput, alertSelect } from "src/ts/alert";
     import SideChatList from "./SideChatList.svelte";
-    import { joinMultiuserRoom } from "src/ts/sync/multiuser";
+    import { ConnectionIsHost, ConnectionOpenStore, joinMultiuserRoom, RoomIdStore } from "src/ts/sync/multiuser";
   import { sideBarSize } from "src/ts/gui/guisize";
   import DevTool from "./DevTool.svelte";
   let sideBarMode = 0;
@@ -659,6 +659,22 @@
       </div>
     {:else if $CurrentCharacter?.chaId === '§playground'}
       <SideChatList bind:chara={ $CurrentCharacter} />
+    {:else if $ConnectionOpenStore}
+      <div class="flex flex-col">
+        <h1 class="text-xl">{language.connectionOpen}</h1>
+        <span class="text-textcolor2 mb-4">{language.connectionOpenInfo}</span>
+        <div class="flex">
+          <span>ID: </span>
+          <span class="text-blue-600">{$RoomIdStore}</span>
+        </div>
+        <div>
+          {#if $ConnectionIsHost}
+            <span class="text-emerald-600">{language.connectionHost}</span>
+          {:else}
+            <span class="text-gray-500">{language.connectionGuest}</span>
+          {/if}
+        </div>
+      </div>
     {:else}
       <div class="w-full h-8 min-h-8 border-l border-b border-r border-selected relative bottom-6 rounded-b-md flex">
         <button on:click={() => {
diff --git a/src/ts/process/index.ts b/src/ts/process/index.ts
index e4a94e19..ee6a17f8 100644
--- a/src/ts/process/index.ts
+++ b/src/ts/process/index.ts
@@ -20,7 +20,7 @@ import { additionalInformations } from "./embedding/addinfo";
 import { cipherChat, decipherChat } from "./cipherChat";
 import { getInlayImage, supportsInlayImage } from "./files/image";
 import { getGenerationModelString } from "./models/modelString";
-import { sendPeerChar } from "../sync/multiuser";
+import { connectionOpen, peerRevertChat, peerSafeCheck, peerSync } from "../sync/multiuser";
 import { runInlayScreen } from "./inlayScreen";
 import { runCharacterJS } from "../plugins/embedscript";
 import { addRerolls } from "./prereroll";
@@ -108,6 +108,19 @@ export async function sendChat(chatProcessIndex = -1,arg:{
     }
     doingChat.set(true)
 
+    if(connectionOpen){
+        chatProcessStage.set(4)
+        const peerSafe = await peerSafeCheck()
+        if(!peerSafe){
+            peerRevertChat()
+            doingChat.set(false)
+            alertError(language.otherUserRequesting)
+            return false
+        }
+        await peerSync()
+        chatProcessStage.set(0)
+    }
+
     let db = get(DataBase)
     let selectedChar = get(selectedCharID)
     const nowChatroom = db.characters[selectedChar]
@@ -1307,7 +1320,7 @@ export async function sendChat(chatProcessIndex = -1,arg:{
 
     chatProcessStage.set(4)
 
-    sendPeerChar()
+    peerSync()
 
     if(req.special){
         if(req.special.emotion){
diff --git a/src/ts/storage/database.ts b/src/ts/storage/database.ts
index 8df5071a..42d99ed7 100644
--- a/src/ts/storage/database.ts
+++ b/src/ts/storage/database.ts
@@ -1062,6 +1062,8 @@ export interface Message{
     chatId?:string
     time?: number
     generationInfo?: MessageGenerationInfo
+    name?:string
+    otherUser?:boolean
 }
 
 export interface MessageGenerationInfo{
diff --git a/src/ts/sync/multiuser.ts b/src/ts/sync/multiuser.ts
index e78a0c18..f370c504 100644
--- a/src/ts/sync/multiuser.ts
+++ b/src/ts/sync/multiuser.ts
@@ -1,23 +1,65 @@
 import { v4 } from 'uuid';
-import { alertError, alertInput, alertNormal, alertWait } from '../alert';
-import { get } from 'svelte/store';
-import { DataBase, setDatabase, type character, saveImage } from '../storage/database';
-import { selectedCharID } from '../stores';
+import { alertError, alertInput, alertNormal, alertStore, alertWait } from '../alert';
+import { get, writable } from 'svelte/store';
+import { DataBase, setDatabase, type character, saveImage, type Chat } from '../storage/database';
+import { CurrentChat, selectedCharID } from '../stores';
 import { findCharacterIndexbyId, sleep } from '../util';
 import type { DataConnection, Peer } from 'peerjs';
 import { readImage } from '../storage/globalApi';
+import { doingChat } from '../process';
 
 async function importPeerJS(){
     return await import('peerjs');
 }
 
+interface ReciveFirst{
+    type: 'receive-char',
+    data: character
+}
+interface RequestFirst{
+    type: 'request-char'
+}
+interface ReciveAsset{
+    type: 'receive-asset',
+    id: string,
+    data: Uint8Array
+}
+interface RequestSync{
+    type: 'request-chat-sync',
+    id: string,
+    data: Chat
+}
+interface ReciveSync{
+    type: 'receive-chat',
+    data: Chat
+}
+interface RequestChatSafe{
+    type: 'request-chat-safe',
+    id: string
+}
+interface ResponseChatSafe{
+    type: 'response-chat-safe'
+    data: boolean,
+    id: string
+}
+interface RequestChat{
+    type: 'request-chat'
+}
+
+type ReciveData = ReciveFirst|RequestFirst|ReciveAsset|RequestSync|ReciveSync|RequestChatSafe|ResponseChatSafe|RequestChat
+
 let conn:DataConnection
 let peer:Peer
 let connections:DataConnection[] = []
-let connectionOpen = false
+export let connectionOpen = false
+let requestChatSafeQueue = new Map<string, {remaining:number,safe:boolean,conn?:DataConnection}>()
+export let ConnectionOpenStore = writable(false)
+export let ConnectionIsHost = writable(false)
+export let RoomIdStore = writable('')
 
 export async function createMultiuserRoom(){
     //create a room with webrtc
+    ConnectionIsHost.set(true)
     alertWait("Loading...")
 
     const peerJS = await importPeerJS();
@@ -93,7 +135,96 @@ export async function createMultiuserRoom(){
                     return
                 }
                 char.chats[char.chatPage] = recivedChar.chats[0]
-                sendPeerChar()
+            }
+            if(data.type === 'request-chat-sync'){
+                const db = get(DataBase)
+                const selectedCharId = get(selectedCharID)
+                const char = db.characters[selectedCharId]
+                char.chats[char.chatPage] = data.data
+                db.characters[selectedCharId] = char
+                latestSyncChat = data.data
+                setDatabase(db)
+
+                for(const connection of connections){
+                    if(connection.connectionId === conn.connectionId){
+                        continue
+                    }
+                    const rs:ReciveSync = {
+                        type: 'receive-chat',
+                        data: data.data
+                    }
+                    connection.send(rs)
+                }
+            }
+            if(data.type === 'request-chat'){
+                const db = get(DataBase)
+                const selectedCharId = get(selectedCharID)
+                const char = db.characters[selectedCharId]
+                const chat = char.chats[char.chatPage]
+                const rs:ReciveSync = {
+                    type: 'receive-chat',
+                    data: chat
+                }
+                conn.send(rs)
+            }
+            if(data.type === 'request-chat-safe'){
+                const queue = {
+                    remaining: connections.length,
+                    safe: true,
+                    conn: conn
+                }
+                requestChatSafeQueue.set(data.id, queue)
+                for(const connection of connections){
+                    if(connection.connectionId === conn.connectionId){
+                        queue.remaining--
+                        requestChatSafeQueue.set(data.id, queue)
+                        continue
+                    }
+                    const rs:RequestChatSafe = {
+                        type: 'request-chat-safe',
+                        id: data.id
+                    }
+                    connection.send(rs)
+                }
+                if(queue.remaining === 0){
+                    if(waitingMultiuserId === data.id){
+                        waitingMultiuserId = ''
+                        waitingMultiuserSafe = queue.safe
+                    }
+                    else if(queue.conn){
+                        const rs:ResponseChatSafe = {
+                            type: 'response-chat-safe',
+                            data: queue.safe,
+                            id: data.id
+                        }
+                        queue.conn.send(rs)
+                        requestChatSafeQueue.delete(data.id)
+                    }
+                }
+            }
+            if(data.type === 'response-chat-safe'){
+                const queue = requestChatSafeQueue.get(data.id)
+                if(queue){
+                    queue.remaining--
+                    if(!data.data){
+                        queue.safe = false
+                    }
+                    if(queue.remaining === 0){
+                        if(waitingMultiuserId === data.id){
+                            waitingMultiuserId = ''
+                            waitingMultiuserSafe = queue.safe
+                        }
+                        else if(queue.conn){
+                            const rs:ResponseChatSafe = {
+                                type: 'response-chat-safe',
+                                data: queue.safe,
+                                id: data.id
+                            }
+                            queue.conn.send(rs)
+                            requestChatSafeQueue.delete(data.id)
+                        }
+                    }
+                }
             }
         });
 
@@ -111,28 +242,23 @@ export async function createMultiuserRoom(){
     }
 
     connectionOpen = true
-    alertNormal("Room ID: " + roomId)
+    ConnectionOpenStore.set(true)
+    RoomIdStore.set(roomId)
+    alertStore.set({
+        type: 'none',
+        msg: ''
+    })
     return
 }
 
-interface ReciveFirst{
-    type: 'receive-char',
-    data: character
-}
-interface RequestFirst{
-    type: 'request-char'
-}
-interface ReciveAsset{
-    type: 'receive-asset',
-    id: string,
-    data: Uint8Array
-}
-
-type ReciveData = ReciveFirst|RequestFirst|ReciveAsset
+let waitingMultiuserId = ''
+let waitingMultiuserSafe = false
+let latestSyncChat:Chat|null = null
 
 export async function joinMultiuserRoom(){
 
     //join a room with webrtc
+    ConnectionIsHost.set(false)
     alertWait("Loading...")
     const peerJS = await importPeerJS();
     peer = new peerJS.Peer(
@@ -145,6 +271,7 @@ export async function joinMultiuserRoom(){
     
         let open = false
         conn = peer.connect(roomId);
+        RoomIdStore.set(roomId)
 
         conn.on('open', function() {
             alertWait("Waiting for host to accept connection")
@@ -179,6 +306,32 @@ export async function joinMultiuserRoom(){
                 }
                 case 'receive-asset':{
                     saveImage(data.data, data.id)
+                    break
+                }
+                case 'receive-chat':{
+                    const db = get(DataBase)
+                    const selectedCharId = get(selectedCharID)
+                    const char = structuredClone(db.characters[selectedCharId])
+                    char.chats[char.chatPage] = data.data
+                    db.characters[selectedCharId] = char
+                    latestSyncChat = data.data
+                    setDatabase(db)
+                    break
+                }
+                case 'request-chat-safe':{
+                    const rs:ResponseChatSafe = {
+                        type: 'response-chat-safe',
+                        data: !get(doingChat) || data.id === waitingMultiuserId,
+                        id: data.id
+                    }
+                    conn.send(rs)
+                    break
+                }
+                case 'response-chat-safe':{
+                    if(data.id === waitingMultiuserId){
+                        waitingMultiuserId = ''
+                        waitingMultiuserSafe = data.data
+                    }
                 }
             }
         });
@@ -186,6 +339,7 @@ export async function joinMultiuserRoom(){
         conn.on('close', function() {
             alertError("Connection closed")
             connectionOpen = false
+            ConnectionOpenStore.set(false)
             selectedCharID.set(-1)
         })
     
@@ -199,29 +353,78 @@ export async function joinMultiuserRoom(){
             }
         }        
         connectionOpen = true
+        ConnectionOpenStore.set(true)
         alertNormal("Connected")
     });
     
 }
 
 
-export function sendPeerChar(){
+export async function peerSync(){
     if(!connectionOpen){
         return
     }
+    await sleep(1)
+    const chat = get(CurrentChat)
+    latestSyncChat = chat
     if(!conn){
         // host user
         for(const connection of connections){
             connection.send({
-                type: 'receive-char',
-                data: get(DataBase).characters[get(selectedCharID)]
+                type: 'receive-chat',
+                data: chat
             });
         }
     }
     else{
         conn.send({
-            type: 'receive-char',
-            data: get(DataBase).characters[get(selectedCharID)]
-        });
+            type: 'request-chat-sync',
+            data: chat
+        } as RequestSync)
     }
+}
+
+export async function peerSafeCheck() {
+    if(!connectionOpen){
+        return true
+    }
+    await sleep(500)
+    if(!conn){
+        waitingMultiuserId = v4()
+        requestChatSafeQueue.set(waitingMultiuserId, {
+            remaining: connections.length,
+            safe: true,
+        })
+        for(const connection of connections){
+            const rs:RequestChatSafe = {
+                type: 'request-chat-safe',
+                id: waitingMultiuserId
+            }
+            connection.send(rs)
+        }
+        while(waitingMultiuserId !== ''){
+            await sleep(100)
+        }
+        return waitingMultiuserSafe
+    }
+    else{
+        waitingMultiuserId = v4()
+        const rs:RequestChatSafe = {
+            type: 'request-chat-safe',
+            id: waitingMultiuserId
+        }
+        conn.send(rs)
+        while(waitingMultiuserId !== ''){
+            await sleep(100)
+        }
+        return waitingMultiuserSafe
+
+    }
+}
+
+export function peerRevertChat() {
+    if(!connectionOpen || !latestSyncChat){
+        return
+    }
+    CurrentChat.set(latestSyncChat)
 }
\ No newline at end of file