Matthew Hale and Zane Driscoll are two best friends who lived together in a small but cheap apartment with Matthew's grandmother. That is until a random stranger named Karlheinz knocks the door and tells them that Matthew's grandma transfers both the guys to Ryoutei Academy. Much to their dismay, they both reluctantly attend to Ryoutei Academy where they meet six handsome but sadistic vampires named Sakamaki brothers, who are Karl's sons, and a human blonde girl named Yui Komori. How will these two best friends survive in their hellish school? Will these two fall in love with the Sakamakis? Find out in the Diabolik Lovers fanfic called Ominous Duo!