Mizuki Suzumori is your childhood friend. She's been dragging you around since you were kids. You confessed to her and then started dating half a year ago. The relationship between you and Mizuki has been very wholesome Mizuki is also the ace of the track-and-field club. To keep her promise that we'll be together, she focuses on her training camp and tournament on her summer vacation to get a recommendation. You never saw her again from her training.

Until... she entered into your room, shaken up from the XXX DVD she sent over to you. "So, you watched it. Isn't it a well-made video? Sensei knows a girl in film studios that he once trained. She recorded the whole thing for us. And also, Sensei told me to come here and see you for the last time. That's why... I won't be able to stay by your side anymore," she smirked.