If you're looking for manga similar to Seraph of the End: Guren Ichinose, Resurrection at Nineteen (Light Novel), you might like these titles.
On the corner of Chinatown, the two of them crossed, The boy name is Inumi Haserou, high-school bodyguard who takes 1000 yen for each trouble; the girl name is Nata, self-styled Sage who mysteriously collapsed in the back alley. Deciding to protect Nata, Haserou would have to face the sudden change in his daily peaceful lives, as a group of Vampiric being who consumed people Ki, called [Demonic Sage] starts to attack them. Their purpose: to hunt Nata, who holds the key as the powerful weapons capable of turning them powerless!
“Lores”— substantial forms born out of urban legends. And high-schooler Tsukumo Jin, who had accidentally released the strongest and most well-known “lore of the vampire”, was now the butler (and lover) of Sylvia, the vampire princess who chooses to take on the form of a little girl. Jin was also tasked with saving his beloved little sister Shigure by banishing the “one-man hide-and-seek” urban legend with the help of mysterious transfer student Ayase. It was the beginning of the battle with “the last vampire”, the hidden entity orchestrating these incidents…