diff --git a/src/mfm/toString.ts b/src/mfm/toString.ts
new file mode 100644
index 0000000000..5b53105b32
--- /dev/null
+++ b/src/mfm/toString.ts
@@ -0,0 +1,112 @@
+import { MfmForest, MfmTree } from './prelude';
+import { nyaize } from '../misc/nyaize';
+
+export type RestoreOptions = {
+	doNyaize?: boolean;
+};
+
+export function toString(tokens: MfmForest | null, opts?: RestoreOptions): string {
+
+	if (tokens === null) return '';
+
+	function appendChildren(children: MfmForest, opts?: RestoreOptions): string {
+		return children.map(t => handlers[t.node.type](t, opts)).join('');
+	}
+
+	const handlers: { [key: string]: (token: MfmTree, opts?: RestoreOptions) => string } = {
+		bold(token, opts) {
+			return `**${appendChildren(token.children, opts)}**`;
+		},
+
+		big(token, opts) {
+			return `***${appendChildren(token.children, opts)}***`;
+		},
+
+		small(token, opts) {
+			return `<small>${appendChildren(token.children, opts)}</small>`;
+		},
+
+		strike(token, opts) {
+			return `~~${appendChildren(token.children, opts)}~~`;
+		},
+
+		italic(token, opts) {
+			return `<i>${appendChildren(token.children, opts)}</i>`;
+		},
+
+		motion(token, opts) {
+			return `<motion>${appendChildren(token.children, opts)}</motion>`;
+		},
+
+		spin(token, opts) {
+			return `<spin>${appendChildren(token.children, opts)}</spin>`;
+		},
+
+		jump(token, opts) {
+			return `<jump>${appendChildren(token.children, opts)}</jump>`;
+		},
+
+		flip(token, opts) {
+			return `<flip>${appendChildren(token.children, opts)}</flip>`;
+		},
+
+		blockCode(token) {
+			return `\`\`\`${token.node.props.lang || ''}\n${token.node.props.code}\n\`\`\`\n`;
+		},
+
+		center(token, opts) {
+			return `<center>${appendChildren(token.children, opts)}</center>`;
+		},
+
+		emoji(token) {
+			return (token.node.props.emoji ? token.node.props.emoji : `:${token.node.props.name}:`);
+		},
+
+		hashtag(token) {
+			return `#${token.node.props.hashtag}`;
+		},
+
+		inlineCode(token) {
+			return `\`${token.node.props.code}\``;
+		},
+
+		mathInline(token) {
+			return `\\(${token.node.props.formula}\\)`;
+		},
+
+		mathBlock(token) {
+			return `\\[${token.node.props.formula}\\]`;
+		},
+
+		link(token, opts) {
+			return `[${appendChildren(token.children, opts)}](${token.node.props.url})`;
+		},
+
+		mention(token) {
+			return token.node.props.canonical;
+		},
+
+		quote(token) {
+			return `${appendChildren(token.children, {doNyaize: false}).replace(/^/gm,'>').trim()}\n`;
+		},
+
+		title(token, opts) {
+			return `[${appendChildren(token.children, opts)}]\n`;
+		},
+
+		text(token, opts) {
+			return (opts && opts.doNyaize) ? nyaize(token.node.props.text) : token.node.props.text;
+		},
+
+		url(token) {
+			return `<${token.node.props.url}>`;
+		},
+
+		search(token, opts) {
+			const query = token.node.props.query;
+			return `${(opts && opts.doNyaize ? nyaize(query) : query)} [search]\n`;
+		}
+	};
+
+	return appendChildren(tokens, { doNyaize: (opts && opts.doNyaize) || false }).trim();
+}
diff --git a/src/misc/nyaize.ts b/src/misc/nyaize.ts
index 9fbfc8b500..6ee3b68477 100644
--- a/src/misc/nyaize.ts
+++ b/src/misc/nyaize.ts
@@ -1,8 +1,5 @@
-import rndstr from 'rndstr';
-
 export function nyaize(text: string): string {
-	const [toNyaize, exclusionMap] = exclude(text);
-	const nyaized = toNyaize
+	return text
 		// ja-JP
 		.replace(/な/g, 'にゃ').replace(/ナ/g, 'ニャ').replace(/ﾅ/g, 'ﾆｬ')
 		// en-US
@@ -13,34 +10,4 @@ export function nyaize(text: string): string {
 		))
 		.replace(/(다$)|(다(?=\.))|(다(?= ))|(다(?=!))|(다(?=\?))/gm, '다냥')
 		.replace(/(야(?=\?))|(야$)|(야(?= ))/gm, '냥');
-	return replaceExceptions(nyaized, exclusionMap);
-}
-
-function exclude(text: string): [string, Record<string, string>] {
-	const map: Record<string, string> = {};
-	function substitute(match: string): string {
-		let randomstr: string;
-		do {
-			randomstr = rndstr({ length: 16, chars: '🀀-🀫' });
-		} while(Object.prototype.hasOwnProperty.call(map, randomstr));
-		map[randomstr] = match;
-		return randomstr;
-	}
-	const replaced = text
-		.replace(/```(.+?)?\n([\s\S]+?)```(\n|$)/gm, match => substitute(match)) // code block
-		.replace(/`([^`\n]+?)`/g, match => substitute(match)) // inline code
-		.replace(/(https?:\/\/.*?)(?= |$)/gm, match => substitute(match)) // URL
-		.replace(/:([a-z0-9_+-]+):/gim, match => substitute(match)) // emoji
-		.replace(/#([^\s.,!?'"#:\/\[\]【】]+)/gm, match => substitute(match)) // hashtag
-		.replace(/@\w([\w-]*\w)?(?:@[\w.\-]+\w)?/gm, match => substitute(match)); // mention
-	return [replaced, map];
-}
-
-function replaceExceptions(text: string, map: Record<string, string>): string {
-	for (const rule in map) {
-		if (Object.prototype.hasOwnProperty.call(map, rule)) {
-			text = text.replace(rule, map[rule]);
-		}
-	}
-	return text;
 }
diff --git a/src/models/repositories/note.ts b/src/models/repositories/note.ts
index cc856f2ba1..73d7ad86eb 100644
--- a/src/models/repositories/note.ts
+++ b/src/models/repositories/note.ts
@@ -1,12 +1,13 @@
 import { EntityRepository, Repository, In } from 'typeorm';
 import { Note } from '../entities/note';
 import { User } from '../entities/user';
-import { nyaize } from '../../misc/nyaize';
 import { Emojis, Users, PollVotes, DriveFiles, NoteReactions, Followings, Polls } from '..';
 import { ensure } from '../../prelude/ensure';
 import { SchemaType } from '../../misc/schema';
 import { awaitAll } from '../../prelude/await-all';
 import { convertLegacyReaction, convertLegacyReactions } from '../../misc/reaction-lib';
+import { toString } from '../../mfm/toString';
+import { parse } from '../../mfm/parse';
 
 export type PackedNote = SchemaType<typeof packedNoteSchema>;
 
@@ -217,7 +218,8 @@ export class NoteRepository extends Repository<Note> {
 		});
 
 		if (packed.user.isCat && packed.text) {
-			packed.text = nyaize(packed.text);
+			const tokens = packed.text ? parse(packed.text) : [];
+			packed.text = toString(tokens, { doNyaize: true });
 		}
 
 		if (!opts.skipHide) {