Irozuku Monochrome

The romantic comedy manga centers on protagonist Isshiki, who falls in love with a virgin who is maintaining her chastity. Unfortunately, Isshiki gets possessed by the demon of lust Asmodeus, and he does everything to stimulate girls' sexual desires to get Isshiki excited. To be able to exorcise the demon, Isshiki must not get excited no matter what. It's the ultimate battle between eroticism and purity. (Source: ANN)