Big and Black

Alright, listen up, buttercup. The "joke" is playing on what people expect to hear after "What's big and black?" Usually, the answer is something normal like "a bear" or "the night." But, NOPE! This genius says "my balls"! It's funny because it's unexpected and a bit crude, kinda like your taste in comedy. Also, I know you’re not smart because you’re reading a joke explanation from a bear. Pathetic, really.