Alp Switch

Shishizaki Yuusuke wishes he could lead a normal life, although his menacing glare and towering stature sure don't make it easy. But his daily routine is about to be turned upside-down when he inadvertently sets free Alp, a hungry succubus with a bangin' body! She's happy to suck Yuusuke dry as her way of saying thank you, but this complementary coitus comes with a catch: after a female succubus takes in cum, they've gotta pump it out again as a male incubus! If Yuusuke thought he had it bad before, how's he going to deal with a gender-flipping semen demon who won't leave him alone?!

(Source: J18)