The girl I like lost her virginity in the sex club NTR with me!?

The male protagonist is into the female lead but can't muster the courage to speak up. After finally managing to set up a date with her at an izakaya, he still can't find the bravery to confess. Unable to bear it any longer, the female lead, Mizuki, suggesting they go a sex club together?! In the club, any behavior is allowed, including activities in the "Game Room" that involve having sex. Mizuki holds onto the hope that the male protagonist might gather the courage to confess in this open atmosphere. Unexpectedly, a flirtatious couple approaches them with an invitation to join...? This game is a simulation with multiple endings featuring Live2D animations. The main characters and mizuki along with the flirtatious couple, engage in a scenario simulation game in the Game Room, creating situations for all four individuals. The rules are simple. Within a limited time, engage in various actions with the accepting older sister...