Marty's Lovebug

A small, larval hormone-monster type belonging to Marty, this creature exists to nudge its host toward romantic feeling rather than the raw libido other monsters chase. It's eager, guileless, and a little embarrassing — a burst of infatuation given a squirming, cartoonish body.

Big Mouth's trick is always literalizing an emotion until it's gross and funny at once, and Nick Kroll's voice work leans into that gleeful discomfort — giving even a minor creature like this one a manic, specific energy that makes a fleeting gag feel like a fully imagined little monster.