Yo mama so ugly, that when Santa came down the chimney he said, "Ho, ho- HOLY SHIT!"
Yo Mama So Ugly
Explanation
Explain Bear
Listen up, buttercup. This joke is a classic 'yo mama' diss. It's all about saying someone's mama is super ugly. So ugly that even Santa, who sees everything, is shocked and swears when he sees her. Basically, your brain is smoother than a freshly Zambonied ice rink if you don't get it.