Uke is a demon slayer in the East. Lately demons from the west have been coming over and the east has no means of dealing with them. Uke gets possessed by an incubus, our seme, and as it goes with incubi, seme rapes uke for his lifeforce. Yaoi magic and after a while uke begins to like seme. After some trails, they end up together. The rape isn't cool, but since it's a demon....I guess it's a bit more understandable? BTW, this isn't a humanoid demon, this is monster fucking. Pretty ok read.
Otoshi-Ai