Ryunosuke Yanagida turns bright red whenever he gets flustered. He harbors a deep insecurity: He can't look a girl in the eye. One night, Ryunosuke accidentally witnesses his next-door neighbor, Ami Sasaki, pleasuring herself. And to top it off, Akari is not just anyone—she's a popular girl in his class. But Ami has a secret of her own, a "hidden condition" she can't tell anyone about. Sharing their secrets sparks a special connection between them. Thus begins their school life together! This is the start of an ultra-awkward yet intensely sensitive, youthful, ecchi romantic comedy.