From MangaHelpers: The new demon king, Vermot the 13th, is bored of his life in the demon kingdom, so he decides to take over the human world. He heads there with his sword and his pretty maid, Sara. With his powers and abilities, he is easily able to take over the first kingdom he targets, reduce the surviving princess to his pet, and slaughter any righteous heroes that come his way. He loves how he can take whatever he wants with his own power in this new life, rather than it already having been given to him (as in the demon world). He's not planning to stop his conquest anytime soon.
Okinodoku Desu Ga, Bouken No Sho Wa Maou No Mono Ni Narimashita. - Raw Chapter 35
Okinodoku Desu Ga, Bouken No Sho Wa Maou No Mono Ni Narimashita. - Raw Chapter 36