BAGR-066 A slutty little sister who distorts the friendship and sexuality of her otaku brother, Seira Kuwahara

A geeky college student starts living alone after moving to college. His younger sister, envious of her brother, begins frequenting his room. One day, she tries to negotiate with him to borrow his room so she can have sex with her sex friend, but he declines, saying that his friends will be coming over. Troubled, the younger sister suddenly comes up with a diabolical idea and decides to put it into action... As she continues to mentally torture her brother, she awakens to her sadistic side...