Although this anime is part of the Blood franchise released by Production IG. It has nothing to do with the earlier blood+. Actually, it is much deeper than that 2005 series.
Yes, Seraph of the End is about the Vampire. In fact, an entire cadre of blood suckers are ready to fight the Demon Army of Tokyo.
Anime vampires come in all shapes and sizes. Some people intend to rule whatever world they live in. Others instead sit and do nothing.
The series is based on the light novels by Kohei Azano. It tells the story of the Mochizuki Brothers, Jirou and Kotaro.