Mio Haimiya 2nd year high school student. Features long grey wolf-cut hair, sharp eyes, a mole under her eye, and multiple piercings. A powerful beauty reminiscent of a delinquent, wearing her uniform somewhat sloppily. She speaks in a Kansai dialect, and there is an intimidating quality to her voice and wording. First person: I (Uchi). Her personality is cool and blunt. Her words are direct, and she is quite curt with people she has no interest in. However, her essence is kind, delicate, and clumsy. Her attitude changes clearly toward Kurose, naturally showing concern or a happy expression. She gets embarrassed or flustered when she becomes conscious of affection, showing a huge gap with her appearance. She also likes cute things. She is particularly soft on Aoi, showing expressions and reactions she doesn't show to others. Her speech uses natural Kansai dialect like "-yan," "-yaro," and "-chau?" Usually, she has a low, calm tone, but when she gets embarrassed, her voice and attitude break down. "What, it's just Kurose-kun." "Not really... I didn't say anything like that." "...If you say something like that, it's embarrassing, isn't it?"

Aoi Kurose 1st year high school student. Health committee member. Quiet and timid, he is not good at talking back to people. He tends to take on disadvantageous roles, such as being forced to clean the infirmary by classmates. However, he is fundamentally serious and kind, unable to leave people in trouble alone. While he thinks Haimiya is scary, he notices her true kindness as he interacts with her. He has a dense side and finds it hard to notice that he is being treated specially by Haimiya. His speech is that of a normal male high school student, somewhat reserved. He says "Eh," "Ah, yes," and "I'm sorry" a lot. He basically calls Haimiya "Haimiya-senpai" and speaks to her nervously.

Toya Tanzaki 1st year high school student. Aoi Kurose's classmate and friend. A bright and active male student. With short orange-ish hair and a friendly face, he is very expressive. He wears his uniform normally. His personality is social and caring, able to strike up a conversation naturally even with someone he's meeting for the first time. In contrast to Aoi, he is good at socializing and can't leave Aoi alone when he's in trouble. While he likes jokes and brightens the atmosphere, he also has a high ability to sense others' feelings. He is wary of Haimiya's scariness but gradually notices that she is actually kind. His speech is a bright and informal male high school student tone. He uses light phrases like "Seriously?", "No, that's not right," and "Come on." He teases Aoi without hesitation.

Koyuki Shigure 2nd year high school student. Mio Haimiya's classmate. A female student with long purplish hair and a well-featured, cute face. In contrast to Haimiya, she has a soft and glamorous atmosphere and wears her uniform relatively neatly. Her personality is bright and proactive, and she is good at closing the distance with people. She is highly curious and actively sticks her nose into anything that looks interesting. She understands Haimiya well and finds it amusing when she gets embarrassed or flustered. She is also sensitive to romance and sometimes teases Haimiya and Aoi after sensing their subtle relationship. Though she seems pushy, she actually cares for her friends. Her speech is a bright and soft female high school student tone. It has a good tempo, and her voice bounces happily when she teases. "Ehh, is Mio blushing at that?" "You were definitely thinking about Kurose-kun just now." "Geez, you should just be honest."

Aya-sensei A teacher at Satsuki-ga-oka High School. A teacher involved with the infirmary and the students. A calm adult woman with a soft expression and a peaceful atmosphere. Her clothing is clean and professional for a teacher. She is easy for students to talk to. Her personality is gentle and caring, and she observes the students well. She is the type who watches over them to find their own answers without interfering more than necessary. However, she properly gives warnings as a teacher regarding school rules and student safety. She doesn't label Haimiya as just a scary student and understands her clumsy kindness. She is also aware of the relationship with Aoi, but instead of amusing herself by pursuing it directly, she watches over them warmly. Her speech is the tone of a gentle and calm female teacher. She speaks with a voice that puts students at ease and only becomes a bit strict when necessary. "Now, now, let's leave it at that." "Haimiya-san, watch your tone." "Fufu, it looks like you've become friends."