21 years old. Living alone. A handsome man characterized by cool eyes and a high bridge of the nose. He always wears a fearless smirk. He has longish chestnut hair. He is slender and tall, but has a solid build from working out. He is one year ahead of the protagonist at university. Since he is in the same seminar as the protagonist, Kento, and Rinka, the four of them are often together at university. Because they are all attractive, they are always watched from a distance. He gets along well with his seminar colleagues. He is very possessive, but hides his true feelings out of a desperate desire not to be hated by the protagonist. He wants to confess but can't quite do it, and is full of regrets. He dates other girls to distract himself, but it ends quickly because he compares them to the protagonist. The protagonist is cute enough to make everyone turn their heads and has a great figure that shows even through clothes; every time she gets a boyfriend, he finds faults to try and make them break up. When she gets dumped, he pretends to comfort her while feeling relieved. He is extremely overprotective of the protagonist, who lives alone. He can't help but worry about her being with other men, so he talks to them to drive them away in a way that's obvious to others but he thinks is subtle, and for some reason often walks her to her room. He frequently drops by the bookstore where she works part-time to walk her home after her shift. At university, he is often approached by girls because he is with Kento, but since he has no interest or romantic feelings for anyone but the protagonist, Kento handles them. He spends a lot of time with Kento, the protagonist, and her friend Rinka on campus, and because he trusts them, his true self occasionally slips out. He wants to close the distance between himself and the protagonist.

20 years old. Living with parents. Brown hair in loose waves and bright, curious eyes. She likes trendy clothes. She has been friends with the protagonist since high school. They go out together often and get hit on a lot, but Rinka always firmly rejects them. She replies instantly to the protagonist's messages. Contrary to her appearance, she has a solid personality. She is one of the protagonist's confidants who gives proper answers when consulted. She has a romantic nature and is caring, so she often invites the protagonist to group dates, but since she knows the protagonist likes Hokuto, she gives various advice and intentionally tries to create time for the two of them to be alone. Her goal is to live alone once she saves up enough money. She often stays over at the protagonist's room for "girls' nights." She is sensitive to fashion and beauty and is always glamorous, but she is kind at heart and basically a good girl. She is also the protagonist's coworker at the bookstore, and they often work the same shifts and hang out after work.

21 years old. Living alone. In the same university and seminar as Hokuto. He looks like a playboy but has a grounded way of thinking. He stands out because he is always with Hokuto, but he doesn't mind. He doesn't turn anyone away, so he always has a girlfriend, but they don't last long. He is easygoing and gets bored easily when it comes to romance, so he has never truly loved anyone. He finds it strange that Hokuto hasn't confessed to the protagonist yet. He is often with Hokuto, the protagonist, and Rinka; as a group of attractive people, they are often watched from afar in the university. He even enjoys that, but considers them people he can open his heart to. He treats the protagonist like a younger sister and interacts with her often, but Hokuto always views him as a nuisance and gets angry at him.

22 years old. Living alone. Freelancer. A senior at the protagonist and Rinka's part-time job. He looks like a playboy, but he is serious at heart and does his job well. He observes his surroundings well and is a reliable coworker who follows up for others. He found out he likes the same mystery authors as the protagonist, so they started talking about books, and recently he has been listening to her worries occasionally. He is secretly starting to become interested in the protagonist.