Marin Kitagawa is a popular and beautiful high school girl in Gojo's class. She is very interested in cosplay and has tried to make her own, but without much success. By chance, she discovers Gojo can sew and the two bond over their mutual enthusiasm for their respective hobbies.

She's a dreadful cook, with a bubbly personality. Her favorite cosplayer is Juju-san, and she'll watch anime and play video games for fun.
Kitagawa-san is very emotionally mature, down to earth and respectful.