diff --git a/packages/frontend/assets/kawaii/LICENSE_SAWARATSUKI_KawaiiLogos b/packages/frontend/assets/kawaii/LICENSE_SAWARATSUKI_KawaiiLogos
new file mode 100644
index 000000000..d09912f27
--- /dev/null
+++ b/packages/frontend/assets/kawaii/LICENSE_SAWARATSUKI_KawaiiLogos
@@ -0,0 +1,18 @@
+LICENSE
+-------
+
+Copyright (c) by [さわらつき](https://github.com/SAWARATSUKI)
+
+The following files:
+
+- misskey-io.png
+- about-icon.png
+
+are licensed under proprietary license. To view a copy of this license, visit https://github.com/SAWARATSUKI/KawaiiLogos/blob/main/README_EN.md#license
+AND SHOULD NOT be considered as part of this project, which is licensed under AGPL-3.0-only.
+
+The following files:
+
+- about-icon.png (uwl.png)
+
+were copied from [misskey-dev/misskey-hub-next](https://github.com/misskey-dev/misskey-hub-next/tree/221a89760e80d75a00600c4e37e22c0f226a6017/public/img/uwu)
diff --git a/packages/frontend/assets/kawaii/about-icon.png b/packages/frontend/assets/kawaii/about-icon.png
new file mode 100644
index 000000000..e85cabba7
Binary files /dev/null and b/packages/frontend/assets/kawaii/about-icon.png differ
diff --git a/packages/frontend/assets/kawaii/misskey-io.png b/packages/frontend/assets/kawaii/misskey-io.png
new file mode 100644
index 000000000..110c2d50b
Binary files /dev/null and b/packages/frontend/assets/kawaii/misskey-io.png differ
diff --git a/packages/frontend/src/boot/common.ts b/packages/frontend/src/boot/common.ts
index d86ae18ff..1f459bb86 100644
--- a/packages/frontend/src/boot/common.ts
+++ b/packages/frontend/src/boot/common.ts
@@ -124,8 +124,8 @@ export async function common(createVue: () => App<Element>) {
 		miLocalStorage.setItem('v', instance.version);
 	});
 
-	//#region loginId
 	const params = new URLSearchParams(location.search);
+	//#region loginId
 	const loginId = params.get('loginId');
 
 	if (loginId) {
@@ -142,6 +142,17 @@ export async function common(createVue: () => App<Element>) {
 	}
 	//#endregion
 
+	//#region kawaii
+	if (params.has('kawaii') || params.has('uwu')) {
+		const v = params.get('kawaii') ?? params.get('uwu');
+		if (v === 'false' || v === '0' || v === 'no' || v === 'off') {
+			miLocalStorage.removeItem('kawaii');
+		} else {
+			miLocalStorage.setItem('kawaii', 'true');
+		}
+	}
+	//#endregion
+
 	// NOTE: この処理は必ずクライアント更新チェック処理より後に来ること(テーマ再構築のため)
 	watch(defaultStore.reactiveState.darkMode, (darkMode) => {
 		applyTheme(darkMode ? ColdDeviceStorage.get('darkTheme') : ColdDeviceStorage.get('lightTheme'));
diff --git a/packages/frontend/src/components/MkVisitorDashboard.vue b/packages/frontend/src/components/MkVisitorDashboard.vue
index 54333cd4e..6e653ea4c 100644
--- a/packages/frontend/src/components/MkVisitorDashboard.vue
+++ b/packages/frontend/src/components/MkVisitorDashboard.vue
@@ -6,7 +6,8 @@ SPDX-License-Identifier: AGPL-3.0-only
 <template>
 <div v-if="instance" :class="$style.root">
 	<div :class="[$style.main, $style.panel]">
-		<img :src="instance.iconUrl || '/favicon.ico'" alt="" :class="$style.mainIcon"/>
+		<img v-if="miLocalStorage.getItem('kawaii')" src="/client-assets/kawaii/misskey-io.png" alt="Logo by @sawaratsuki@misskey.io" :class="$style.mainIconAlt"/>
+		<img v-else :src="instance.iconUrl || '/favicon.ico'" alt="" :class="$style.mainIcon"/>
 		<button class="_button _acrylic" :class="$style.mainMenu" @click="showMenu"><i class="ti ti-dots"></i></button>
 		<div :class="$style.mainFg">
 			<h1 :class="$style.mainTitle">
@@ -81,6 +82,7 @@ import * as os from '@/os.js';
 import { misskeyApi } from '@/scripts/misskey-api.js';
 import { i18n } from '@/i18n.js';
 import { instance } from '@/instance.js';
+import { miLocalStorage } from '@/local-storage.js';
 import MkNumber from '@/components/MkNumber.vue';
 import XActiveUsersChart from '@/components/MkVisitorDashboard.ActiveUsersChart.vue';
 import { openInstanceMenu } from '@/ui/_common_/common';
@@ -139,6 +141,13 @@ function exploreOtherServers() {
 	filter: drop-shadow(0 2px 5px rgba(0, 0, 0, 0.5));
 }
 
+.mainIconAlt {
+	width: 85%;
+	margin-top: -47px;
+	vertical-align: bottom;
+	filter: drop-shadow(0 2px 5px rgba(0, 0, 0, 0.5));
+}
+
 .mainMenu {
 	position: absolute;
 	top: 16px;
diff --git a/packages/frontend/src/local-storage.ts b/packages/frontend/src/local-storage.ts
index 8029bca68..1cf543886 100644
--- a/packages/frontend/src/local-storage.ts
+++ b/packages/frontend/src/local-storage.ts
@@ -38,7 +38,8 @@ type Keys =
 	`aiscript:${string}` |
 	'lastEmojisFetchedAt' | // DEPRECATED, stored in indexeddb (13.9.0~)
 	'emojis' | // DEPRECATED, stored in indexeddb (13.9.0~);
-	`channelLastReadedAt:${string}`
+	`channelLastReadedAt:${string}` |
+	'kawaii'
 
 export const miLocalStorage = {
 	getItem: (key: Keys): string | null => window.localStorage.getItem(key),
diff --git a/packages/frontend/src/pages/about-misskey.vue b/packages/frontend/src/pages/about-misskey.vue
index 3d33c4447..595f98f81 100644
--- a/packages/frontend/src/pages/about-misskey.vue
+++ b/packages/frontend/src/pages/about-misskey.vue
@@ -11,7 +11,9 @@ SPDX-License-Identifier: AGPL-3.0-only
 			<div class="_gaps_m znqjceqz">
 				<div v-panel class="about">
 					<div ref="containerEl" class="container" :class="{ playing: easterEggEngine != null }">
-						<img src="/client-assets/about-icon.png" alt="" class="icon" draggable="false" @load="iconLoaded" @click="gravity"/>
+						<img v-if="miLocalStorage.getItem('kawaii')" src="/client-assets/kawaii/about-icon.png" alt="" class="iconAlt" draggable="false" @load="iconLoaded" @click="gravity"/>
+						<img v-else src="/client-assets/about-icon.png" alt="" class="icon" draggable="false" @load="iconLoaded" @click="gravity"/>
+						<Mfm v-if="miLocalStorage.getItem('kawaii')" text="Logo by @sawaratsuki@misskey.io" class="iconCredit"/>
 						<div class="misskey">Misskey</div>
 						<div class="version">v{{ version }}</div>
 						<span v-for="emoji in easterEggEmojis" :key="emoji.id" class="emoji" :data-physics-x="emoji.left" :data-physics-y="emoji.top" :class="{ _physics_circle_: !emoji.emoji.startsWith(':') }">
@@ -137,6 +139,7 @@ import { physics } from '@/scripts/physics.js';
 import { i18n } from '@/i18n.js';
 import { instance } from '@/instance.js';
 import { defaultStore } from '@/store.js';
+import { miLocalStorage } from '@/local-storage.js';
 import * as os from '@/os.js';
 import { definePageMetadata } from '@/scripts/page-metadata.js';
 import { claimAchievement, claimedAchievements } from '@/scripts/achievements.js';
@@ -443,6 +446,21 @@ definePageMetadata(() => ({
 				z-index: 1;
 			}
 
+			> .iconAlt {
+				display: block;
+				width: 85%;
+				margin: 0 auto;
+				position: relative;
+				z-index: 1;
+			}
+
+			> .iconCredit {
+				margin: 0 auto;
+				width: max-content;
+				position: relative;
+				z-index: 1;
+			}
+
 			> .misskey {
 				margin: 0.75em auto 0 auto;
 				width: max-content;
diff --git a/packages/frontend/src/pages/about.vue b/packages/frontend/src/pages/about.vue
index e43915680..526724262 100644
--- a/packages/frontend/src/pages/about.vue
+++ b/packages/frontend/src/pages/about.vue
@@ -11,7 +11,9 @@ SPDX-License-Identifier: AGPL-3.0-only
 			<div class="_gaps_m">
 				<div :class="$style.banner" :style="{ backgroundImage: `url(${ instance.bannerUrl })` }">
 					<div style="overflow: clip;">
-						<img :src="instance.iconUrl ?? instance.faviconUrl ?? '/favicon.ico'" alt="" :class="$style.bannerIcon"/>
+						<img v-if="miLocalStorage.getItem('kawaii')" src="/client-assets/kawaii/misskey-io.png" alt="" :class="$style.bannerIconAlt"/>
+						<img v-else :src="instance.iconUrl ?? instance.faviconUrl ?? '/favicon.ico'" alt="" :class="$style.bannerIcon"/>
+						<Mfm v-if="miLocalStorage.getItem('kawaii')" text="Logo by @sawaratsuki@misskey.io" :class="$style.iconCredit"/>
 						<div :class="$style.bannerName">
 							<b>{{ instance.name ?? host }}</b>
 						</div>
@@ -168,6 +170,7 @@ import { i18n } from '@/i18n.js';
 import { definePageMetadata } from '@/scripts/page-metadata.js';
 import { claimAchievement } from '@/scripts/achievements.js';
 import { instance } from '@/instance.js';
+import { miLocalStorage } from '@/local-storage.js';
 
 const props = withDefaults(defineProps<{
 	initialTab?: string;
@@ -230,6 +233,12 @@ definePageMetadata(() => ({
 	border-radius: 8px;
 }
 
+.bannerIconAlt {
+	display: block;
+	margin: 16px auto 0 auto;
+	width: 85%;
+}
+
 .bannerName {
 	display: block;
 	padding: 16px;
@@ -238,6 +247,13 @@ definePageMetadata(() => ({
 	background: linear-gradient(transparent, rgba(0, 0, 0, 0.7));
 }
 
+> .iconCredit {
+	margin: 0 auto;
+	width: max-content;
+	position: relative;
+	z-index: 1;
+}
+
 .rules {
 	counter-reset: item;
 	list-style: none;
diff --git a/packages/frontend/src/pages/user/home.vue b/packages/frontend/src/pages/user/home.vue
index 735b7d2f5..727e5e8af 100644
--- a/packages/frontend/src/pages/user/home.vue
+++ b/packages/frontend/src/pages/user/home.vue
@@ -110,7 +110,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 									<!--
 										*** LICENSE NOTICE ***
 										* This SVG is derived from the https://skeb.jp/ website, All rights reserved to *Skeb Inc.* https://skeb.co.jp/
-										* This resource SHOULD NOT be considered as a part of the this project that has licensed under AGPL-3.0-only
+										* This resource SHOULD NOT be considered as a part of this project that has licensed under AGPL-3.0-only
 									-->
 									<svg class="ti ti-fw" viewBox="0 0 40 40" xmlns="http://www.w3.org/2000/svg">
 										<linearGradient id="a" x1="14.645309%" x2="85.354691%" y1="14.645309%" y2="85.363492%">
diff --git a/packages/frontend/src/scripts/rate-limiter.ts b/packages/frontend/src/scripts/rate-limiter.ts
index 35b459579..3382e3b0e 100644
--- a/packages/frontend/src/scripts/rate-limiter.ts
+++ b/packages/frontend/src/scripts/rate-limiter.ts
@@ -3,7 +3,7 @@
  * SPDX-License-Identifier: ISC
  *
  * This file is derived from the project that has licensed under the ISC license.
- * This file SHOULD NOT be considered as a part of the this project that has licensed under AGPL-3.0-only
+ * This file SHOULD NOT be considered as a part of this project that has licensed under AGPL-3.0-only
  * Adapted from https://github.com/isaacs/ttlcache/blob/b6002f971e122e3b35e23d00ac6a8365d505c14d/examples/rate-limiter-window.ts
  */
 
diff --git a/packages/frontend/src/ui/_common_/navbar.vue b/packages/frontend/src/ui/_common_/navbar.vue
index fa1f0eb8c..447f58383 100644
--- a/packages/frontend/src/ui/_common_/navbar.vue
+++ b/packages/frontend/src/ui/_common_/navbar.vue
@@ -9,7 +9,8 @@ SPDX-License-Identifier: AGPL-3.0-only
 		<div :class="$style.top">
 			<div :class="$style.banner" :style="{ backgroundImage: `url(${ instance.bannerUrl })` }"></div>
 			<button v-tooltip.noDelay.right="instance.name ?? i18n.ts.instance" class="_button" :class="$style.instance" @click="openInstanceMenu">
-				<img :src="instance.iconUrl || instance.faviconUrl || '/favicon.ico'" alt="" :class="$style.instanceIcon"/>
+				<img v-if="miLocalStorage.getItem('kawaii')" src="/client-assets/kawaii/misskey-io.png" alt="" :class="$style.instanceIconAlt"/>
+				<img v-else :src="instance.iconUrl || instance.faviconUrl || '/favicon.ico'" alt="" :class="$style.instanceIcon"/>
 			</button>
 		</div>
 		<div :class="$style.middle">
@@ -68,6 +69,7 @@ import { $i, openAccountMenu as openAccountMenu_ } from '@/account.js';
 import { defaultStore } from '@/store.js';
 import { i18n } from '@/i18n.js';
 import { instance } from '@/instance.js';
+import { miLocalStorage } from '@/local-storage.js';
 
 const iconOnly = ref(false);
 
@@ -173,6 +175,11 @@ function more(ev: MouseEvent) {
 		aspect-ratio: 1;
 	}
 
+	.instanceIconAlt {
+		display: inline-block;
+		width: 85%;
+	}
+
 	.bottom {
 		position: sticky;
 		bottom: 0;