diff --git a/src/routes/index.ts b/src/routes/index.ts
index 89c805b..57d6495 100644
--- a/src/routes/index.ts
+++ b/src/routes/index.ts
@@ -33,7 +33,10 @@ router.post('/toggle-like', (req, res) => {
     const { id, charId } = req.body
 
     if (charLikes[charId]) {
-        charLikes[charId].likes.push(id)
+        const currentLikes = new Set(charLikes[charId].likes)
+        currentLikes.add(id)
+        
+        charLikes[charId].likes = [...currentLikes]
     } else {
         charLikes[charId] = { likes: [id] }
     }