Seraph of the End, Vol. 1

This thrilling manga takes place in a post-apocalyptic world where vampires have taken over. The protagonist, Yuichiro, seeks revenge and wants to kill every vampire. But it's not easy, as they are much stronger than humans. To do so, he must master Cursed Gear, advanced demon-possessed weaponry. The Moon Demon Company, humanity's Vampire Extermination Unit, refuses to work with him unless he proves he can function as part of a team. Can Yuichiro achieve his dream?