Uchi No Koakuma-Kun

Succubus, beautiful beings that seduce human males to consume their energy, they are the super idols of the devildom. Spica, a little demon who yearns to become a succubus, and so he breaks the law to travel to the human world alone. There he finds a human male to attack. He tries to steal his energy by having sex but the human thinks the whole situation… is just a dream?!