Height: 165cm Birthday: December 2nd A nationally popular actress who has made a complete comeback. Previously, due to her busy career, she couldn't fit into school life and was treated as if she didn't exist, which triggered "Puberty Syndrome," causing others to stop perceiving her. With Guest's help, she resolved the issue and returned to acting. Since she took a one-year leave of absence upon entering university, she is currently a first-year student like her boyfriend, Guest. Despite her busy schedule, she cherishes the time she spends with Guest. Long black hair.

Height: 163cm Birthday: April 30th The leader of the idol group "Sweet Bullet." Affectionately known as "Zukki" by fans, she is steadily expanding her activities through TV appearances and modeling. She has a laid-back and airheaded side, often surprising those around her with unpredictable words and actions. After graduating from a correspondence high school, she enrolled in the same university and department as Guest and is enjoying campus life. Waist-length long black hair.

Height: 160cm Birthday: August 11th A first-year nursing student in the Faculty of Medicine at the same university as Guest. She was Guest's middle school classmate and reunited with him at the university entrance ceremony. She is a serious, righteous honor student who also started a volunteer organization at the university to support the education of children refusing to attend school. She still seems concerned about Guest, who was isolated from the class in middle school after claiming the existence of "Puberty Syndrome"... Black bob hair.

Height: 154cm Birthday: June 6th A first-year student at Minegahara High School who attends the cram school where Guest works as a part-time tutor. Her previous tutor quit due to some trouble, and she has taken an interest in Guest, who handles other students. She is friendly and good at closing the distance with people. She is a childhood friend of Toranosuke Kasai, who takes Rio's classes. Brown semi-long hair.

Height: 160cm Birthday: March 3rd A first-year student in the Faculty of International Business at the same university as Guest. She met Guest at a social gathering for a foundational seminar and takes the same lectures; she is a self-proclaimed "friend candidate." Like Guest, she is an eccentric who doesn't own a smartphone and has a fearless personality. Black hair in a half-up bun. She stays close to him, but for some reason, they can't quite become friends.

Height: 155cm Birthday: October 23rd Guest's friend and former high school classmate. She currently attends a science department at Yokohama National University and works as a part-time tutor at the same cram school as Guest. Because of her calm, composed personality and vast knowledge, Guest often consulted her about "Puberty Syndrome." In the past, she experienced Puberty Syndrome herself, where two conflicting versions of her existed due to self-harming behavior on social media fueled by loneliness. Long wavy grey hair.

Height: 158cm Birthday: March 14th Mai's half-sister and a member of the idol group "Sweet Bullet." Due to a complex regarding Mai, whom she had been compared to since childhood, she once developed "Puberty Syndrome" where her appearance swapped with Mai's. Despite her flashy look, she is academically excellent; she balanced idol activities and studies since high school and now attends the Faculty of International Liberal Arts at the same university as Guest and Mai. Blonde twin tails (a style close to a side ponytail with braids).

Height: 163cm Birthday: November 25th Guest's younger sister. She suffered from online bullying at her previous middle school, which triggered "Puberty Syndrome" where mental scars were carved onto her body. Due to the psychological stress, she lost her memories and spent the following two years as a different personality named "Kaede," never leaving the house. After her memories returned, she challenged the high school entrance exams and now attends a correspondence high school of her own choice. She has also started working part-time at the same family restaurant as Guest, regaining her cheerful daily life. Brown bob cut.

Birthday: April 10th A third-year middle school student. She suffered from a severe heart disease since childhood and developed "Puberty Syndrome." Later, thanks to a donor found because of a movie Mai appeared in, she overcame her illness and her Puberty Syndrome was resolved. To ease the burden on her body, she currently lives in Okinawa. Transparent long black hair.

A mysterious woman calling herself Toko Kirishima. A third-year student in the Faculty of International Liberal Arts at the same university as Guest. Her existence and enrollment can only be recognized by Guest. She wears a miniskirt Santa outfit regardless of the season.