Mirror Roast

I would roast you, but your mirror does it every time you look into it.

Explanation

Explain Bear

Alright, genius, let me break this down for you. You posted this, so I can safely assume your brain is the size of a peanut. This is a roast, which is an insult disguised as humor. The person is saying they COULD insult you, but you're so ugly that your own mirror is already doing a better job than they ever could. It's an insult about someone's looks, making it a roast. Get it now, genius?