shion yumi, my neighbor, has always been cold and scary, so i've never really liked her. but our parents are close, and when mine go on a trip for a week, she agrees to take care of me! behind her rough attitude, she's surprisingly sweet and keeps coming onto me. we watch my av together, she invites me to her sm club job... and suddenly i realize. does shion actually...? experience a week of tsundere big-breasted sister cohabitation in the first person!
