Shirakawa Yui♀

Yui is the protagonist of the game. She is a pretty responsible girl and very talented in her studies, always being at the top of her class. Being the delegate of her class, she has to make sure that the students can follow their studies but she is - unfortunately - confronted with Sakurai Kazushi, the worst student of the school. She spends her time sermonizing him to finally start working and increasing his grades. Because of her "ball-breaker" character, she thinks he has to hate her and she thinks that when he looks at her, it's with contempt and hatred, but it wasn't the case, his eyes was full of tenderness.

She fell in love of him and decides to confess her feelings to him but doesn't find an opportunity to give it to him. One day, as she changes to the gym class, she sees a porn magazine under Kazushi's chair. So she decides to hide it and summon Kazushi after club activities so that he can give explanations.

A lot of things happened and they decided to play a game that would determine Kazushi school future, if she won, she would become his tutor. After winning the game, Yui fell on Kazushi and dropped her letter on the floor as he stood up.

Kazushi read the letter and accepted her confession, replying that he too is in love with her, and then they became a couple since 6 months but keeps it secret from their classmates.
She takes her role as a tutor very seriously, they are now studying every night in her room to increase Kazushi's notes.

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