Sexual Bank: Sister Was Surprisingly Hot Too

A visual novel about a NEET shut-in named Shingo whose mundane existence—eating, sleeping, gaming, and fantasizing about his sister—is disrupted when a strange employee from a "sperm bank" offers him a deal: in exchange for collecting his wasted sexual energy, they will help him seduce his real sister during her 14-day visit home. The game is structured around a two-phase day cycle: daytime interactions with the sister to raise her "obscenity value" and lower her "rationality," and nighttime scenes that play out based on player choices and accumulated stats. Success requires careful stat management and strategic dialogue choices.