Ha Hakdog
This is how you roast someone who's too clueless to realize you're making them look like a fool. It's like giving a slap to a person who thinks they're invincible.
Ha Hakdog! You're like a kid who didn't know the teacher was watching.
Ha Hakdog! You're so clueless you think you're the only one who talks.
Ha Hakdog! You're like a ghost who doesn't know it's being haunted.