Peanut Butter and Jellyfish

Alright, listen up, buttercup. The joke is that sharks are supposed to eat fish, right? But instead of eating a regular fish sandwich, this shark likes a "peanut butter and jellyfish" sandwich. It's funny because it's unexpected and jellyfish are kinda weird and slimy. I bet you eat peanut butter and jelly, you uncreative genius.