Sumire is a timid and timid geek who loves erotic novels so much that she secretly masturbates in the classroom. One day, when she goes to deliver homework to her childhood friend Tatsuya, who is on the verge of failing, she is surprised to find a morning erection! Curious to see a man's organ for the first time, she can't resist and inserts it raw into her pussy! Sumire becomes addicted to the pleasure of her first experience and the hard cock, and discovers the joys of sex. From that day on, she starts milking semen everywhere...! She wiggles her firm ass in the living room and rides the man's horny cock until he cums inside her! Even though her friends are there, she secretly gives him a handjob in the classroom, causing him to ejaculate explosively! She cums over and over again in the nurse's office, pistoning and cumming five times without pulling out! Sex feels so good... it's the best!