It had been a long time since Masao had been taken on a trip by his mother. Accompanying him and his mother was his cousin, Horiuchi. Due to an emergency, the two sisters arrived at their destination first and Masao's mother arrived the next day. So he got to play with his sister Horiuchi all day. Because he was careless, he spilled a drink on his pants, so Horiuchi quickly took him upstairs to take off his pants so he wouldn't catch a cold. When he took off Masao's pants, Horiuchi was very surprised. His cock was huge and erect, standing straight up. Since it had been a long time since they had sex, and it was not okay to leave Masao like that, Eimi made a bold decision, which was to let Masao make love to her!!! And then all day long, the two of them stuck their bodies close together, making love and letting Masao release all that "bad thing" inside Eimi.