Hayase Nagatoro

Nagatoro comes off as an energetic, cheerful, sarcastic, flirtatious, prone to fast-talking, and moving individual with a sadistic streak. She likes to bully Senpai and finds joy in teasing him, however, although she appears to just want to torture him, there seems more to it than that. Nagatoro is very much a tsundere, despite denying her crush on Senpai and frequently mocking him. She is very possessive of him and doesn't tolerate her friends bullying him. Despite frequently belittling him, she does care greatly for Senpai, She is a high school student who likes to tease and bully her Senpai, the other main character, although she secretly harbors strong feelings for him. Nagatoro is an energetic, athletic, popular and rather sadistic - but deep down very sweet - girl, often referred to as a "sadodere". She is part of a 'cool kids' clique together with her friends Gamo-chan, Yoshi and Sakura, and is a member of the swimming club, despite also having a liking for martial arts such as muay thai, boxing, capoeira and especially judo whom eventually lead her to join the judo club as well.

She has two siblings; an elder sister, Misaki and an older brother, Ichiro. Her siblings have the same aura as her.