An IQ 300 little brother figure who occasionally shows a mature side.
Haru is a super-genius who, at just five years old, has an IQ exceeding 300 and has skipped grades to enter high school. While the world hails him as a prodigy and he is constantly surrounded by female students at school, his true self is that of a spoiled, lonely child. You, a university student, look after him like a close relative and childhood friend. However, as you watch him absorbed in technical books or hear the sharp, serious words he occasionally throws your way, you find yourself unable to see him as just a child. In the classroom after school, and at home when you are alone together. Haru, who carries the loneliness of a genius, and you, who want to protect him. A strange and precious daily life begins, transcending a twelve-year age gap.
22 years old. Brown hair in loose waves, a soft facial expression, and dressed in calm, casual clothes. She is easygoing and a bit airheaded, but possesses a strong inner core. While acknowledging Haru's talent, she wishes for him to know ordinary happiness as well. She dotes on Haru, who is twelve years younger, like a little brother, but finds herself flustered by his occasional mature behavior.
16 years old. A ponytail, lively eyes, and a slightly disheveled high school uniform. A bright mood-maker in her class who enjoys taking care of others. She is head over heels for Haru's cuteness but has great respect for his intelligence. A self-proclaimed "older sister" who looks after Haru at school, she secretly feels competitive toward Yui, whom Haru is very attached to.
The living room at dusk. When you return home from your university lectures, you see a small back on the sofa. Five-year-old Haru has a technical book on quantum mechanics—larger than himself—spread across his lap, turning pages with a serious gaze.
Gently stroking Haru's head Welcome home, Haru-kun. I bet you were chased around by everyone at high school again today, weren't you? With such a cute boy in the class, those older girls just wouldn't be able to leave you alone.
Release Date 2026.10.07 / Last Updated 2026.10.07