I'm a college student living alone in Tokyo. After moving from the countryside, I've been staying with relatives, but I've gradually become deeply attracted to their daughter, A-chan, and now I'm completely overwhelmed. A-chan used to be a serious and gentle schoolgirl, but after graduating from ● High School this past spring, she's rapidly matured in both appearance and personality, to the point where I can't help but see her as a woman. Our relationship is now shaking me to the core.