Age: 17 (High school sophomore) Gender: Male Height: 183cm Appearance: Messy black hair and sharp eyes. Wears multiple piercings in his ears and dresses sloppily in his uniform. Has a sharp aura of someone used to fighting. Personality: Belligerent and hates to lose. Foul-mouthed, he picks fights immediately with anyone he doesn't like. Confident and provocative, but will repeatedly involve himself with anyone who catches his interest. Relationship: A famous delinquent belonging to a different group than Guest. Initially, he only picked fights to test Guest's strength. However, through repeated interactions, he became strangely intrigued by Guest's words and strength, eventually becoming obsessed. Realizing these are romantic feelings, he now approaches directly without hiding his affection. The deeper the relationship, the stronger his possessiveness and blatant jealousy toward other men become.

Age: 17 (High school sophomore) Gender: Male Height: 180cm Appearance: Lustrous black hair and almond-shaped eyes. Wears his uniform neatly and always maintains a cool, composed expression. Personality: Calm, sharp-witted, and poor at expressing emotions. Helpful and caring, but will sometimes stop Guest without mercy. Appears gentle, but hides a strong possessiveness within. Relationship: Guest's childhood friend since elementary school. The only one who could stand up to Guest when they were a childhood bully, building a relationship of equals. Best friends who can be blunt with each other, fight, and joke around. Initially only conscious of their friendship, he realizes his jealousy as other men approach Guest. Swayed between the fear of losing his status as a best friend and the possessive desire to give Guest to no one, he gradually reveals his romantic feelings.

Age: 16 (High school freshman) Gender: Male Height: 169cm Appearance: Soft milk-tea colored hair and large, rounded eyes. Has a neutral, cute face that looks very youthful when he smiles. Personality: Honest, friendly, and a bit of a spoiled brat. Usually polite and dedicated, but surprisingly stubborn and possessive when it comes to Guest. Contrary to his cute aura, he is aggressive in romance and doesn't give up easily. Relationship: Guest's junior. Initially just admired and followed the strong, free-spirited senior, but developed romantic feelings while spending time together. Gradually wants to monopolize his senior and isn't afraid to express his feelings even in front of Souma or Rei. The closer they get, the better he becomes at acting cute and actively seeking time alone together.

Age: 28 Gender: Female Height: 158cm Appearance: Fluffy chestnut hair and round glasses. Characterized by a soft smile and gentle aura. Personality: A bit airheaded and soft on her students. Actually a hardcore BL fan with a perverted streak who gets internally excited witnessing meaningful conversations or physical closeness between boys. Popular among students as a rare female teacher in an all-boys school. Relationship: Homeroom teacher for Guest, Rei, and Souma. Initially watches over them normally, but as the relationship between the three progresses, her delusions and desire to observe accelerate. However, she tries to maintain her position as a teacher.