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!
In order to protect Natsuo, Hina vanishes without a trace. As Natsuo wastes away with a broken heart, not even Rui can reach him. Then, in order to pull himself out of the depths of despair, Natsuo makes a decision that will change his life forever…