diff --git a/locales/index.d.ts b/locales/index.d.ts
index 4bc906b3c..ca4b75b51 100644
--- a/locales/index.d.ts
+++ b/locales/index.d.ts
@@ -5371,6 +5371,14 @@ export interface Locale extends ILocale {
      * この情報は他のユーザーには公開されません。
      */
     "thisInfoIsNotVisibleOtherUser": string;
+    /**
+     * 水に流す
+     */
+    "flushItAway": string;
+    /**
+     * 削除をしても全てが水に流れるわけではありませんが
+     */
+    "deleteNotWash": string;
     "_bubbleGame": {
         /**
          * 遊び方
diff --git a/locales/ja-JP.yml b/locales/ja-JP.yml
index 1d1dc7857..2aad7056b 100644
--- a/locales/ja-JP.yml
+++ b/locales/ja-JP.yml
@@ -1336,6 +1336,8 @@ setScheduledTime: "予約日時を設定"
 willBePostedAt: "{x}に投稿されます"
 sensitiveByModerator: "管理者によって、ドライブのファイルがセンシティブとして設定されました。\n詳細については、[NSFWガイドライン](https://go.misskey.io/media-guideline)を確認してください。"
 thisInfoIsNotVisibleOtherUser: "この情報は他のユーザーには公開されません。"
+flushItAway: "水に流す"
+deleteNotWash: "削除をしても全てが水に流れるわけではありませんが"
 
 _bubbleGame:
   howToPlay: "遊び方"
diff --git a/packages/frontend/assets/sounds/flush.mp3 b/packages/frontend/assets/sounds/flush.mp3
new file mode 100644
index 000000000..9ec98f9fd
Binary files /dev/null and b/packages/frontend/assets/sounds/flush.mp3 differ
diff --git a/packages/frontend/src/components/MkDateSeparatedList.vue b/packages/frontend/src/components/MkDateSeparatedList.vue
index 7c9463af2..8345f1b51 100644
--- a/packages/frontend/src/components/MkDateSeparatedList.vue
+++ b/packages/frontend/src/components/MkDateSeparatedList.vue
@@ -11,6 +11,7 @@ import { i18n } from '@/i18n.js';
 import * as os from '@/os.js';
 import { defaultStore } from '@/store.js';
 import { MisskeyEntity } from '@/types/date-separated-list.js';
+import { isAprilFoolsDay } from '@/scripts/seasonal-events';
 
 export default defineComponent({
 	props: {
@@ -119,12 +120,16 @@ export default defineComponent({
 		};
 
 		function onBeforeLeave(element: Element) {
+			if (isAprilFoolsDay()) return;
+
 			const el = element as HTMLElement;
 			el.style.top = `${el.offsetTop}px`;
 			el.style.left = `${el.offsetLeft}px`;
 		}
 
 		function onLeaveCancelled(element: Element) {
+			if (isAprilFoolsDay()) return;
+
 			const el = element as HTMLElement;
 			el.style.top = '';
 			el.style.left = '';
@@ -136,6 +141,7 @@ export default defineComponent({
 			[$style['date-separated-list-nogap']]: props.noGap,
 			[$style['direction-down']]: props.direction === 'down',
 			[$style['direction-up']]: props.direction === 'up',
+			[$style['april-fool']]: isAprilFoolsDay(),
 		};
 
 		return () => defaultStore.state.animation ? h(TransitionGroup, {
@@ -210,6 +216,14 @@ export default defineComponent({
 	}
 }
 
+.direction-up.april-fool ,
+.direction-down.april-fool {
+	&:global > .list-enter-from,
+	&:global > .list-leave-to {
+		animation: components-MkDateSeparatedList-spin-shrink 3s ease-in forwards;
+	}
+}
+
 .separator {
 	text-align: center;
 }
@@ -240,5 +254,16 @@ export default defineComponent({
 .date-2-icon {
 	margin-left: 8px;
 }
+
+@keyframes spin-shrink {
+	0% {
+		transform: rotate(0deg) scale(1);
+		opacity: 1;
+	}
+	100% {
+		transform: rotate(2160deg) scale(0);
+		opacity: 0;
+	}
+}
 </style>
 
diff --git a/packages/frontend/src/scripts/get-note-menu.ts b/packages/frontend/src/scripts/get-note-menu.ts
index b7d3c1abf..3d3f40b29 100644
--- a/packages/frontend/src/scripts/get-note-menu.ts
+++ b/packages/frontend/src/scripts/get-note-menu.ts
@@ -20,6 +20,8 @@ import { clipsCache } from '@/cache.js';
 import { MenuItem } from '@/types/menu.js';
 import MkRippleEffect from '@/components/MkRippleEffect.vue';
 import { isSupportShare } from '@/scripts/navigator.js';
+import { isMute, playUrl } from '@/scripts/sound';
+import { isAprilFoolsDay } from '@/scripts/seasonal-events';
 
 export async function getNoteClipMenu(props: {
 	note: Misskey.entities.Note;
@@ -180,10 +182,14 @@ export function getNoteMenu(props: {
 	function del(): void {
 		os.confirm({
 			type: 'warning',
-			text: i18n.ts.noteDeleteConfirm,
+			text: isAprilFoolsDay() ? i18n.ts.deleteNotWash + '\n' + i18n.ts.noteDeleteConfirm : i18n.ts.noteDeleteConfirm,
 		}).then(({ canceled }) => {
 			if (canceled) return;
 
+			if (isAprilFoolsDay()) {
+				if (!isMute()) playUrl('/client-assets/sounds/flush.mp3', {});
+			}
+
 			misskeyApi('notes/delete', {
 				noteId: appearNote.id,
 			});
@@ -435,8 +441,8 @@ export function getNoteMenu(props: {
 					action: delEdit,
 				} : undefined,
 				{
-					icon: 'ti ti-trash',
-					text: i18n.ts.delete,
+					icon: isAprilFoolsDay() ? 'ti ti-whirl' : 'ti ti-trash',
+					text: isAprilFoolsDay() ? i18n.ts.flushItAway : i18n.ts.delete,
 					danger: true,
 					action: del,
 				}]
diff --git a/packages/frontend/src/scripts/seasonal-events.ts b/packages/frontend/src/scripts/seasonal-events.ts
new file mode 100644
index 000000000..8209517c8
--- /dev/null
+++ b/packages/frontend/src/scripts/seasonal-events.ts
@@ -0,0 +1,47 @@
+enum EventTypes {
+	Christmas = 0,
+	NewYear = 1,
+	ValentinesDay = 2,
+	Halloween = 3,
+	AprilFoolsDay = 4,
+	Unknown = 5
+}
+
+export const isEventDay = (): EventTypes => {
+	const date = new Date();
+	const month = date.getMonth();
+	const day = date.getDate();
+
+	// jsで月を0から始まる
+	// 例えば4月は月の値が3になる
+	if (month === 11 && day === 25) return EventTypes.Christmas;
+	if (month === 0 && day === 1) return EventTypes.NewYear;
+	if (month === 1 && day === 14) return EventTypes.ValentinesDay;
+	if (month === 9 && day === 31) return EventTypes.Halloween;
+	if (month === 3 && day === 1) return EventTypes.AprilFoolsDay;
+	return EventTypes.Unknown;
+};
+
+export const isAprilFoolsDay = (): boolean => {
+	return isEventDay() === EventTypes.AprilFoolsDay;
+};
+
+export const isChristmas = (): boolean => {
+	return isEventDay() === EventTypes.Christmas;
+};
+
+export const isNewYear = (): boolean => {
+	return isEventDay() === EventTypes.NewYear;
+};
+
+export const isValentinesDay = (): boolean => {
+	return isEventDay() === EventTypes.ValentinesDay;
+};
+
+export const isHalloween = (): boolean => {
+	return isEventDay() === EventTypes.Halloween;
+};
+
+export const isUnknown = (): boolean => {
+	return isEventDay() === EventTypes.Unknown;
+};