Onii-chan ... why didn't you help me ... It's been half a year since her younger sister Nana, who had been worn by men until it became shabby and was dyed cloudy and kept polluted, was ruthlessly thrown onto the road ... His older brother, Ryoichi, who finally decided to move to revenge, was approaching the target as a teacher and was asking for the opportunity. Oh, why, what are you doing, stop Ryoichi with beautiful girls going to the villa Ryoichi, who unknowingly fixed the door and made it as a closed room that could not escape, humiliated Ruriko at the beginning. She glares at her mouth and forcibly pours a cloudy lips into her pharynx and forcibly opens her unwetted lips. Ruriko crying for her first pain and fear is ruthlessly pushed up ... Aoi, Natsuki, Mako, Kanami who run away. In her ears Ruriko's sorrowful cry echoing from her separate room clings to her ...