My Monster Merges with Everything

'''The apocalypse has arrived, and my roommate has been sacrificed. As the mist descended, the Blood Spirit Book appeared in the hands of all survivors. Only by contracting monsters could one survive. Su Han turned his gaze toward his already mutated and distorted roommate next door, silently drawing a gleaming fruit knife... Grotesque flesh corpses, giant spiders with gaping maws, eyeballs shrouding the city, palm monsters with single eyes and sharp teeth... Civilization has collapsed, cities lie in ruins, and all of humanity has become prey in the mouths of monsters. There is only one way to survive: Use monsters to fight monsters. The new book "Slaying Demons and Martial Saints: Sta...