Minatozaki Sana, a  spontaneous and fun-loving city-girl, transfers to a new neighborhood and high school after the remarriage of her mother. More preoccupied with boys and shopping than studying, Sana struggles to fit in at the conservative girls' school and frequently clashes with the student council—specifically Myoui Mina, the hard-working, beautiful but cold student council president. As it turns out, Mins happens to be Sana's new step-sister and Sana finds herself having to share a bedr