Iku Iku Succubus

You are Tanehisa Busujima, a middle-aged teacher at a private academy who speaks his mind, and can't hide his massive dick and lusty thoughts. You ogle the thighs of female teachers when they wear tight skirts, and gaze at the pert asses of schoolgirls when they wear bloomers.
Obviously, the accusations of sexual harassment are piling up, and you're on the merge of getting sacked.

The principal leaves you with one option to continue your profession: become an instructor for an exchange student from the Succubus Kingdom. Most people don't know, but a land of lusty succubi exists. On top of that, the Japanese government is trying to solve the depleted birth rate problem by making a contract with these succubi, in hopes that the dream demons will make the young men uncontrollably horny.

On the outside, the exchange program involves teaching the succubi about the human world, but in truth, the goal of the program is to reeducate failed succubi about the pleasure of sex. Clearly, your particular skillset fits the instructor role like a glove.

Strap in, because this intense sexual class is in session!

[From DLsite]