Owari no Seraph - Part 1 English: Seraph of the End: Vampire Reign Japanese: 終わりのセラフ
One day, a mysterious virus appeared on Earth which killed every infected human over the age of 13. At the same time, vampires emerged from the world’s dark recesses and enslaved mankind. Enter Hyakuya Yuuichirou, a young boy, who along with the rest of the children from his orphanage, are treated as livestock by the vampires. Even in captivity, Yuuichirou dreams big. He dreams of killing vampires. He dreams of killing them all.
English: Devils and Realist Japanese:
魔界王子 devils and realist
The noble William possesses a rare kind of intelligence. The school he attends and his family background both draw much attention. However, one day, his family loses money after his uncle’s business fails. Worrying about how this would affect his school's reputation, he returns home to help the family butler search for things to sell. What they found was an underground room that had been used by William’s ancestors. The room contains a magical seal, with which William unintentionally summons a demon. The demon, Dantalion tells William that has the ability to choose the king of the demon world! Naturally, the candidates for king will come after William…who will become king in the end?!