diff --git a/gradle.properties b/gradle.properties
index a1972de..5667829 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,6 +1,6 @@
 ## Core
 
-VERSION = 0.5.2.0
+VERSION = 0.5.2.1
 
 # dependencies
 
diff --git a/src/main/java/cc/sukazyo/cono/morny/GradleProjectConfigures.java b/src/main/java/cc/sukazyo/cono/morny/GradleProjectConfigures.java
index 6718b5e..8d7906c 100644
--- a/src/main/java/cc/sukazyo/cono/morny/GradleProjectConfigures.java
+++ b/src/main/java/cc/sukazyo/cono/morny/GradleProjectConfigures.java
@@ -4,6 +4,6 @@ package cc.sukazyo.cono.morny;
  * the final field that will be updated by gradle automatically.
  */
 public class GradleProjectConfigures {
-	public static final String VERSION = "0.5.2.0";
-	public static final long COMPILE_TIMESTAMP = 1646742061976L;
+	public static final String VERSION = "0.5.2.1";
+	public static final long COMPILE_TIMESTAMP = 1647170439025L;
 }
diff --git a/src/main/java/cc/sukazyo/cono/morny/bot/event/EventListeners.java b/src/main/java/cc/sukazyo/cono/morny/bot/event/EventListeners.java
index 3920a57..4eca5a5 100644
--- a/src/main/java/cc/sukazyo/cono/morny/bot/event/EventListeners.java
+++ b/src/main/java/cc/sukazyo/cono/morny/bot/event/EventListeners.java
@@ -11,11 +11,13 @@ public class EventListeners {
 	public static final OnInlineQueries INLINE_QUERY = new OnInlineQueries();
 	public static final OnCallMe CALL_ME = new OnCallMe();
 	public static final OnEventHackHandle EVENT_HACK_HANDLE = new OnEventHackHandle();
+	public static final OnKuohuanhuanNeedSleep KUOHUANHUAN_NEED_SLEEP = new OnKuohuanhuanNeedSleep();
 	
 	public static void registerAllListeners () {
 		EventListenerManager.addListener(
 				ACTIVITY_RECORDER,
 				UPDATE_TIMESTAMP_OFFSET_LOCK,
+				KUOHUANHUAN_NEED_SLEEP,
 				COMMANDS_LISTENER,
 				USER_SLASH_ACTION,
 				INLINE_QUERY,
diff --git a/src/main/java/cc/sukazyo/cono/morny/bot/event/OnKuohuanhuanNeedSleep.java b/src/main/java/cc/sukazyo/cono/morny/bot/event/OnKuohuanhuanNeedSleep.java
new file mode 100644
index 0000000..3c7101c
--- /dev/null
+++ b/src/main/java/cc/sukazyo/cono/morny/bot/event/OnKuohuanhuanNeedSleep.java
@@ -0,0 +1,32 @@
+package cc.sukazyo.cono.morny.bot.event;
+
+import cc.sukazyo.cono.morny.MornyCoeur;
+import cc.sukazyo.cono.morny.bot.api.EventListener;
+import com.pengrad.telegrambot.model.Update;
+import com.pengrad.telegrambot.request.DeleteMessage;
+
+import javax.annotation.Nonnull;
+import java.util.Calendar;
+import java.util.GregorianCalendar;
+import java.util.Locale;
+
+public class OnKuohuanhuanNeedSleep extends EventListener {
+	
+	@Override
+	public boolean onMessage (@Nonnull Update update) {
+		if (
+				update.message().from().id() == 786563752L && (
+						new GregorianCalendar(Locale.TAIWAN).get(Calendar.HOUR_OF_DAY) >= 23 ||
+						new GregorianCalendar(Locale.TAIWAN).get(Calendar.HOUR_OF_DAY) < 5
+				)
+		) {
+			MornyCoeur.extra().exec(
+					new DeleteMessage(update.message().chat().id(),
+							update.message().messageId())
+			);
+			return true;
+		}
+		return false;
+	}
+	
+}