In a city known as "the Hole", a clan of Sorcerers have been snatching people off the streets to use as guinea pigs for "experiments". In a dark alley, Nikaidou found Kaiman, a man with a reptile head and no memories. To undo his curse, they're hunting and killing Sorcerers in the Hole, hoping that eventually they'll kill the right one. When En, the head Sorcerer, gets word of a lizard-man slaughtering people, he sends a crew of "cleaners" into the Hole, igniting a war. (Summary by JonSmith)