My Incubi Harem

From time to time, incubi cross the portal between worlds to choose from among the hottest men on Earth who will be the next incubi king. To be the chosen one, Ciras' master starts to cheat the process and the demons appear before the expected date to find out how anyone would dare to interfere in the process. Will Ciras save his boss or will he tell the incubi the truth? Who is the next chosen one?