FSDSS-534 A plain college student with large breasts outgrows her virgin boyfriend's sex drive and becomes a insatiable big-breasted sister. Aihiko Honjo.

I, a virgin, finally got my first girlfriend, Ai-chan. She's plain-looking but has an amazing figure and is really a good girl. However, her love for me is too heavy... Her looks change day by day, and her sex drive increases. It's fine that she wants to be liked so much that she becomes cute and erotic, but it's gradually becoming uncontrollable. She's turning into a full-blown mental case, and the heavyweight love and sex drive are crushing me.