OniAi (2012)

Young and charming Akiko can hardly contain her excitement as she prepares to reunite with her handsome older brother, Akito, whom she hasn’t seen in years. Her enthusiasm for living together again might be a bit over the top, fueled by her strong brother complex and a desire for his undivided attention. However, their peaceful time together is disrupted when three stunning girls from the student council move in as well. Akito's dream of a quiet life is shattered, and he’ll need to navigate the affections of both his devoted little sister and her alluring competition!