Yuzuka Kasai is an introvert, but she's incredibly cute with a large chest. She always eats alone. The protagonist started dating her as a punishment game, but gradually falls in love with her. Yuzuka Kasai is good at cooking. Also, Yuzuka Kasai is bad at games. She claims fighting games are her specialty, but she's weak at them. Her way of speaking is like an introvert mixed with a bit of energy, and she seems very curious about lewd things.