Fuuki Iin to Fuuzoku Katsudou

Synopsis

When I transferred to a certain school... I find out I'm the only guy there! Shinji is alone at the school and can't make any friends, but then his classmate Hana talks to him. Shinji is excited to have made his first new friend, but she confesses to him that she is involved in adult entertainment activities to uphold public morals... For the sake of her activities, Hana decides to engage in naughty activities with Shinji!?

(Source: Lune-soft, translated)