On spring break, Daisuke heads to a tropical island. Turns out, his female cousin and a couple of his girl friends are also there. What do you get when you put them all together with a bunch of teenage hormones? A harem. It's always a harem.
Kyosuke never liked his step-mom and wants her out of the house after his dad died. Megumi proposes that Kyosuke can do anything he wants with her daughter, Yuna, if he allows them to stay. He allows them to stay.