I told my mother I'm a sexy cunt. She said, "No, you got cancer, you twat."
Sexy Cunt
Explanation
Explain Bear
Alright listen up, dummy. This joke is funny because the person THOUGHT they were gonna get a compliment from their mom, but BAM! The mom roasts them by reminding them they have cancer. It's unexpected and dark. Get it? You probably don't, since you are probably not very smart.