hi im a confused otaku --a few months back i read this newly released manga wc is set in a vampire infested world,it describes how this guy with two guns undergo his final exam to be an agent of this global vampire hunting organization - his goal is to look for the vampire who massacred his whole family,he was partnered with a girl (using twin blades as weapons i think)but on their first mission this protagonist almost got killed and his partner eventually saved him and is revealed that she is the vampire queen,the first and the mother of all vampires--- any ideas bout the title guys???? help :(