High schooler Natsuo is hopelessly in love with his cheerful and popular teacher, Hina. However, one day at a mixer, he meets a moody girl by the name of Rui and ends up sleeping with her. Soon after, his father announces that he's getting remarried to a woman with two daughters of her own. And who shows up in tow, other than both Hina and Rui?! Natsuo's outrageous new life starts now!
“Let’s settle this by the end of the cultural festival.” On a stormy night, Natsuo finds himself alone in bed with a naked Rui. But just when it seems like the miscommunication between them will finally end…! Now with Al and Momo going for the kill, the love square rapidly reaches the climax! Just who will end up with who…?