Meatball Machine Kodoku(蠱毒 ミートボールマシン)

Nobody knows where they came from. They parasitize in human beings, take control of them and change their bodies into hideous monsters or Necro-borgs. When Yuji and Kaoru, both of whom have dark secrets within themselves, get caught up in the horrific battles of Necro-borg, their fates lie in mystery and misery.