Carroll is a Cloud Person that Finn encounters in the episode "The Tower." She used to be a body of water, but after growing tired of people swimming in her, she evaporated. She at first mistakes Finn for one such swimmer, calling him a "real swim nut" after face-blasting him with her lightning gun. Carroll becomes nicer to Finn once she finds out he is having problems and is not a swimmer, and even offers him some advice. She lives in a cloud house that can be flown around.
Carroll is a Cloud Person. She is puffy, small, and has stubby limbs. She has cloud 'hair' that covers her left eye.