Mr. Boner(2017)

The adult part-time jobber was suffering from "impossible" at a young age, but it can be cured by the treatment of Sakuo, who is a senior at the university and is known as a counselor who is thrilling now. However, the penis was always in a full erection state because the libido that had been suppressed until then was released at once. Moreover, adults had no sexual experience until then and did not know how to love women. And I will entrust myself to the temptation of Sakuo, who has been more interested in adults than before.