"Hey, Sōsuke! Let's go play!" - Karen speaks her first lines in which she asks if Sōsuke can play with her.
Karen is a minor character in Ponyo on the Cliff by the Sea directed by Hayao Miyazaki of Studio Ghibli. Sōsuke and Kumiko are her best friends. She is a student in Himawari Nursery School. Sōsuke first meets her in the film after he brings his pet soon-to-become best friend Ponyo to school.
Karen has brown hair and pink bows on her pigtails. She wears a light-pink shirt and darker pink pants. She has a light-green elephant plush toy that she carries around all the time.
Karen becomes quickly offended when Sōsuke didn't give in to her demands.
In kindergarten, Sōsuke tries to hide Ponyo. Karen goes to him. Then she asks him to play with her. But he refuses to do so. She turns her back and goes away, rather annoyed. Sōsuke uses the opportunity to look after Ponyo.