Is this a Zombie? (Light Novel)

Ayumu was murdered by a serial killer – at least, he was. For after the mysterious Eucliwood Hellsythe revives him, he changes from a human to a zombie, much to his dismay. Now, in addition to being unable to die, Ayumu must see to the whims of his supernatural, silent companion – but things continue to get worse from there. As once Ayumu accidentally steals a magical girl named Haruna's powers, he is tasked with the embarrassing, obnoxious task of being a magical girl – err, boy– in her stead! Then with the addition of a hostile vampire ninja to his household, can Ayumu manage to maintain his new home life, fight against attacking monsters, and track down the person who killed him all while attempting to keep what little dignity he has left in tact?