MG-008 Female school friends secretly masturbate next to sex

A couple of school girls and their friends. When she realizes that she is playing with everyone after school, time passes, and her fatigue from studying and club activities comes out. She says, "Let's take a nap," and while everyone is sleeping in the shape of a river... something strange happens to the friend couple next to her. A couple who thinks her friend is sleeping and starts having sex secretly and a friend who secretly masturbates to it. Enjoy the thrill of each other and get excited. Such a sexual experience of youth that is secret to each other.