diff --git a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/ContactImpl.kt b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/ContactImpl.kt
index ada894249..2d740a1f4 100644
--- a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/ContactImpl.kt
+++ b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/ContactImpl.kt
@@ -306,20 +306,19 @@ internal class MemberImpl(
 }
 
 internal class MemberInfoImpl(
-    private val jceInfo: StTroopMemberInfo,
-    private val groupOwnerId: Long
+    jceInfo: StTroopMemberInfo,
+    groupOwnerId: Long
 ) : MemberInfo {
-    override val uin: Long get() = jceInfo.memberUin
-    override val nameCard: String get() = jceInfo.sName ?: ""
-    override val nick: String get() = jceInfo.nick
-    override val permission: MemberPermission
-        get() = when {
-            jceInfo.memberUin == groupOwnerId -> MemberPermission.OWNER
-            jceInfo.dwFlag == 1L -> MemberPermission.ADMINISTRATOR
-            else -> MemberPermission.MEMBER
-        }
-    override val specialTitle: String get() = jceInfo.sSpecialTitle ?: ""
-    override val muteTimestamp: Int get() = jceInfo.dwShutupTimestap?.toInt() ?: 0
+    override val uin: Long = jceInfo.memberUin
+    override val nameCard: String = jceInfo.sName ?: ""
+    override val nick: String = jceInfo.nick
+    override val permission: MemberPermission = when {
+        jceInfo.memberUin == groupOwnerId -> MemberPermission.OWNER
+        jceInfo.dwFlag == 1L -> MemberPermission.ADMINISTRATOR
+        else -> MemberPermission.MEMBER
+    }
+    override val specialTitle: String = jceInfo.sSpecialTitle ?: ""
+    override val muteTimestamp: Int = jceInfo.dwShutupTimestap?.toInt() ?: 0
 }
 
 /**
diff --git a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/chat/receive/OnlinePush.kt b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/chat/receive/OnlinePush.kt
index 06720d94e..8f1ab906c 100644
--- a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/chat/receive/OnlinePush.kt
+++ b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/chat/receive/OnlinePush.kt
@@ -74,8 +74,6 @@ internal class OnlinePush {
             // println(pbPushMsg.msg.msgBody.richText.contentToString())
             val flags = extraInfo?.flags ?: 0
             return GroupMessage(
-                bot = bot,
-                group = group,
                 senderName = pbPushMsg.msg.msgHead.groupInfo.groupCard,
                 sender = group[pbPushMsg.msg.msgHead.fromUin],
                 message = pbPushMsg.msg.toMessageChain(),
diff --git a/mirai-core/src/androidMain/kotlin/net/mamoe/mirai/message/MessagePacket.kt b/mirai-core/src/androidMain/kotlin/net/mamoe/mirai/message/MessagePacket.kt
index 25d9e7640..a9172742c 100644
--- a/mirai-core/src/androidMain/kotlin/net/mamoe/mirai/message/MessagePacket.kt
+++ b/mirai-core/src/androidMain/kotlin/net/mamoe/mirai/message/MessagePacket.kt
@@ -9,7 +9,6 @@
 
 package net.mamoe.mirai.message
 
-import net.mamoe.mirai.Bot
 import net.mamoe.mirai.contact.Contact
 import net.mamoe.mirai.contact.QQ
 import net.mamoe.mirai.utils.MiraiInternalAPI
@@ -18,7 +17,7 @@ import net.mamoe.mirai.utils.MiraiInternalAPI
  * 平台相关扩展
  */
 @UseExperimental(MiraiInternalAPI::class)
-actual abstract class MessagePacket<TSender : QQ, TSubject : Contact> actual constructor(bot: Bot) : MessagePacketBase<TSender, TSubject>(bot) {
+actual abstract class MessagePacket<TSender : QQ, TSubject : Contact> actual constructor() : MessagePacketBase<TSender, TSubject>() {
     //   suspend inline fun uploadImage(image: Bitmap): Image = subject.uploadImage(image)
     //suspend inline fun uploadImage(image: URL): Image = subject.uploadImage(image)
     //suspend inline fun uploadImage(image: Input): Image = subject.uploadImage(image)
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/FriendMessage.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/FriendMessage.kt
index 8ead2fe6a..d4d03120b 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/FriendMessage.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/FriendMessage.kt
@@ -13,12 +13,16 @@ import net.mamoe.mirai.Bot
 import net.mamoe.mirai.contact.QQ
 import net.mamoe.mirai.event.BroadcastControllable
 import net.mamoe.mirai.message.data.MessageChain
+import net.mamoe.mirai.utils.getValue
+import net.mamoe.mirai.utils.unsafeWeakRef
 
 class FriendMessage(
     bot: Bot,
-    override val sender: QQ,
+    sender: QQ,
     override val message: MessageChain
-) : MessagePacket<QQ, QQ>(bot), BroadcastControllable {
+) : MessagePacket<QQ, QQ>(), BroadcastControllable {
+    override val sender: QQ by sender.unsafeWeakRef()
+    override val bot: Bot get() = sender.bot
     override val subject: QQ get() = sender
 
     override fun toString(): String = "FriendMessage(sender=${sender.id}, message=$message)"
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/GroupMessage.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/GroupMessage.kt
index f14d0689e..5752b8755 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/GroupMessage.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/GroupMessage.kt
@@ -22,8 +22,6 @@ import kotlin.jvm.JvmName
 
 @Suppress("unused", "NOTHING_TO_INLINE")
 class GroupMessage(
-    bot: Bot,
-    group: Group,
     val senderName: String,
     /**
      * 发送方权限.
@@ -31,9 +29,10 @@ class GroupMessage(
     val permission: MemberPermission,
     sender: Member,
     override val message: MessageChain
-) : MessagePacket<Member, Group>(bot), Event {
-    val group: Group by group.unsafeWeakRef()
+) : MessagePacket<Member, Group>(), Event {
     override val sender: Member by sender.unsafeWeakRef()
+    val group: Group get() = sender.group
+    override val bot: Bot get() = sender.bot
 
     override val subject: Group get() = group
 
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/MessagePacket.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/MessagePacket.kt
index 0bfd0a01e..36c19d890 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/MessagePacket.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/message/MessagePacket.kt
@@ -32,18 +32,19 @@ import kotlin.jvm.JvmName
  * 请查看各平台的 `actual` 实现的说明.
  */
 @UseExperimental(MiraiInternalAPI::class)
-expect abstract class MessagePacket<TSender : QQ, TSubject : Contact>(bot: Bot) : MessagePacketBase<TSender, TSubject>
+expect abstract class MessagePacket<TSender : QQ, TSubject : Contact>() : MessagePacketBase<TSender, TSubject>
 
 /**
  * 仅内部使用, 请使用 [MessagePacket]
  */ // Tips: 在 IntelliJ 中 (左侧边栏) 打开 `Structure`, 可查看类结构
 @Suppress("NOTHING_TO_INLINE", "UNCHECKED_CAST")
 @MiraiInternalAPI
-abstract class MessagePacketBase<TSender : QQ, TSubject : Contact>(_bot: Bot) : Packet, BotEvent {
+abstract class MessagePacketBase<TSender : QQ, TSubject : Contact> : Packet, BotEvent {
     /**
      * 接受到这条消息的
      */
-    override val bot: Bot by _bot.unsafeWeakRef()
+    @WeakRefProperty
+    abstract override val bot: Bot
 
     /**
      * 消息事件主体.
@@ -53,6 +54,7 @@ abstract class MessagePacketBase<TSender : QQ, TSubject : Contact>(_bot: Bot) :
      *
      * 在回复消息时, 可通过 [subject] 作为回复对象
      */
+    @WeakRefProperty
     abstract val subject: TSubject
 
     /**
@@ -60,6 +62,7 @@ abstract class MessagePacketBase<TSender : QQ, TSubject : Contact>(_bot: Bot) :
      *
      * 在好友消息时为 [QQ] 的实例, 在群消息时为 [Member] 的实例
      */
+    @WeakRefProperty
     abstract val sender: TSender
 
     /**
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/message/MessagePacket.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/message/MessagePacket.kt
index 6d3ca3cbc..389598f07 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/message/MessagePacket.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/message/MessagePacket.kt
@@ -16,7 +16,6 @@ import kotlinx.coroutines.withContext
 import kotlinx.io.core.Input
 import kotlinx.io.core.use
 import kotlinx.io.streams.inputStream
-import net.mamoe.mirai.Bot
 import net.mamoe.mirai.contact.Contact
 import net.mamoe.mirai.contact.QQ
 import net.mamoe.mirai.message.data.Image
@@ -35,7 +34,7 @@ import javax.imageio.ImageIO
  * JVM 平台相关扩展
  */
 @UseExperimental(MiraiInternalAPI::class)
-actual abstract class MessagePacket<TSender : QQ, TSubject : Contact> actual constructor(bot: Bot) : MessagePacketBase<TSender, TSubject>(bot) {
+actual abstract class MessagePacket<TSender : QQ, TSubject : Contact> actual constructor() : MessagePacketBase<TSender, TSubject>() {
     // region 上传图片
     suspend inline fun uploadImage(image: BufferedImage): Image = subject.uploadImage(image)