MC’s father remarried to a woman with a gorgeous little sister. He wasn’t surprised since he knew well how dissolute his father is. But the bright side is mc now get to live together with his sexy sister in law, Azusa. During their introduction, he can’t take his eyes off her big breasts. One day, mc accidentally entered the bathroom without knowing Asuka was inside, Azusa noticed his lewd gaze and decide to play along. When his parents went to a trip, Asuka offers her body to mc, to do whatever he likes with her body.