DVAJ-686 - I'm a gloomy guy who is made to watch over a bad couple having sex at school, but after the fact, a girl who is not satisfied with her premature ejaculation boyfriend secretly invites me to be a substitute dick

Plot: I'm a gloomy guy who is made to watch over a bad couple having sex at school, but after the fact, a girl who is not satisfied with her premature ejaculation boyfriend secretly invites me to be a substitute dick and I spend my days fucking and cumming inside her