[Diabolik lovers: Demon king guardian.]

Lucifer hertzog albedus was a demon king who lived over 1000+ years. In his demon palace he ruled over the demon world so called hell, you must think it was nice and fun to rule a world right? but no it wasn't. He was bored, the only think that he could do was torture sinners and do paperwork, he didn't like to live like that at all, but that was his fate as a immortal demon king. But one day a priest summoned him to protect his daughter where she would leave the church to live with some "relatives" amused agreed the demon king on the priest's request which would of course cost him his soul, what will happen now? will the demon king kill all of the vampire brothers (and the mukami bros ofc) and blow up the school? or will he resist doing that until the contract with the priest is done?

YUI IS A NICE BITCH!! she sometimes hates on the oc and sometimes doesn't.