When their parents are no longer in the picture, a brother decides that he is going to care for his younger sister. Soon enough his intentions turn sour and lewd thoughts enter his brain...he starts touching her at nighttime while he thinks she is sleeping, little does he know that she is only pretending to be asleep...

“I’m all yours…” “I lied about being confessed to,” she says the day they cross the line. Akira can’t get these words out of his head since that day and Yui acts as if nothing happened that day. Seeing her so innocent, Akira vows to not want to be more than just siblings. One day, Akira sees Yui about to take sleeping pills. Yui explain that swallowing these will let someone sleep soundly. That night, Akira stands beside Yui sleeping. All he can think about is ravaging her. Giving in to his hearts desires, when morning comes, he acts as if they’re just two siblings who have a good relationship. Every time he sees Yui taking the pills, he uses that as a chance to repeat the cycle.