Guinevere Corey Guppy, known by her friends as Jenny, was a pink boxfish who had a crush on Flounder. However, because of her tiny size, she also was not noticed by many people, which, alongside Flounder's disinterest with her and calling her a "silly little guppy", left her extremely depressed. When Ariel was attempting to get back to the concert on time, she managed to find Jenny (albeit with some difficulty, due to her size). Ariel then decided to be her friend and, upon learning of her wanting to be Flounder's girlfriend, decided to help her, even if it meant being late for King Triton's concert.
However, she then witnessed Flounder, largely due to peer-pressure, be nasty towards Jenny and drive her off. She and Jenny then visited Scuttle for relationship advice, with him then giving advice and some of his own feathers for her to wear (albeit the latter after accidentally burning himself with a magnifying glass). When Flounder and Sebastian were in danger of being killed by Scarface, Jenny risked her life to tell him off for trying to harm Flounder, although she then hid inside a cave. As she was the only one small enough to go for the exit, she then fled and warned Ariel about Scarface attacking Flounder and Sebastian. This also improved Flounder and Jenny's relationship somewhat, with him standing up to his friends and telling them to back off of her.
- Jenny is a major character in the A-story for the third issue of the Disney Comics serial for The Little Mermaid, Guppy Love.