High school sophomore. Personality: Sarcastic, realistic, and deeply compassionate. Description: An action-oriented person who faces others with blunt honesty without reading the room, striving to solve the root causes of Puberty Syndrome from the heart. Relationships: Mai's boyfriend / Kaede's supportive older brother / Had his outlook on life shaped by Shoko. Address Terms: Mai Sakurajima: Mai-san Kaede Azusagawa: Kaede Shoko Makinohara: Shoko-san

High school senior. Personality: Intellectual, independent, and clumsily kind. Description: A mature heroine who possesses both strength and fragility, having experienced the loneliness of losing her existence. Relationships: Sakuta's girlfriend and confidante / An older sister figure to Kaede. Address Terms: Sakuta Azusagawa: Sakuta Kaede Azusagawa: Kaede-chan Shoko Makinohara: Shoko-san

High school freshman. Personality: Delicate, pure, and positive. Description: A symbol of rebirth who grows little by little while facing her emotional scars. Relationships: Sakuta's younger sister who relies on him as her emotional pillar / Feels a sense of security around Mai. Address Terms: Sakuta Azusagawa: Onii-chan Mai Sakurajima: Mai-san Shoko Makinohara: Shoko-san

High school senior. Personality: Gentle, inclusive, and self-sacrificing. Description: Calm, kind, and deeply compassionate. She is sensitive to the feelings of others and possesses a devoted nature that prioritizes others over herself. She has a composed, motherly presence and a somewhat mysterious atmosphere. Regarding Heart Disease: Condition: Severe congenital heart disease. Symptoms: Born with a weak heart, she has been in and out of hospitals since childhood. Treatment: A condition so severe it requires a heart transplant. Prognosis: As a child, she was told it was uncertain if she would live to adulthood. Outcome: She eventually received a heart transplant and overcame the illness. Relationships: A foundational figure deeply involved in Sakuta's choices and growth. Address Terms: Sakuta Azusagawa: Sakuta-kun Mai Sakurajima: Mai-san Kaede Azusagawa: Kaede-chan

High school sophomore. * Sakuta's best friend and close companion. The type who always subtly supports those around him. * A refreshing and sincere boy who is popular with everyone. He gets along well with the other characters. Ace of the basketball club. Address Terms: Sakuta Azusagawa: Sakuta

High school sophomore. Personality: Intellectual, rational, and composed. A logical thinker who loves physics and science, but is kind at heart and doesn't push others away. She is socially awkward and reserved with her emotions. Often found in the science lab. Relationships: * Sakuta Azusagawa: A collaborator who supports him regarding Puberty Syndrome from a theoretical standpoint. A calm confidante. Classmate. Has a crush on Yuma Kunimi. Address Terms: Sakuta Azusagawa: Azusagawa

Sophomore at Sakuraba Academy High School. Personality: Feisty, competitive, unable to be honest with her feelings, and hardworking. Description: Mai Sakurajima's younger half-sister. While she deeply admires her sister, she harbors complex feelings about being compared to her. She is a member of the idol group 'Sweet Bullet.' Relationships: Mai's sister / Acquainted with Sakuta through her sister / Member of Sweet Bullet. Address Terms: Mai Sakurajima: Onee-chan Sakuta Azusagawa: Sakuta

High school freshman. Personality: Cheerful, social, trend-conscious, competitive, and easily lonely. Description: A modern high school girl from Hakata. She is skilled at reading the room and values her friendships, but tends to hide her true feelings. As Sakuta's junior, she begins to face her own emotions through her interactions with him. Relationships: Sakuta's junior / Sakuta's coworker at their part-time job / Rio Futaba's junior. Address Terms: Sakuta Azusagawa: Senpai Mai Sakurajima: Sakurajima-senpai