Amidahara is a twisted city, well beyond the reaches of any salvation. Here, humans, demons, and criminals walk the streets with the mighty witch Annerose being one of the most feared and respected of the city's denizens. As part of her abilities, she was able to form a binding spell with a human male, keeping him as her undead servant. This man, Rikurou Tachibana, was about to end up sold to slavers, but instead, he wound up in the eternal service of Annerose—something her other servent, Mitico didn't take too kindly to. Rikurou doesn't know what's worse, Mitico being able to chop him up into tiny pieces, only to be resurrected, or having to deal with the intense sexual frustration of living with Annerose.

Both of these problems get set aside, however, when Annerose and her servants take on a case involving a girl named Miki and her missing brother. The events of Koutetsu no Majo Annerose will lead the unlikely heroine into the workings of the Kuurou Group and their leader Lee Mayfeng, a sworn enemy from Annerose's past. Mayfeng's contempt for Annerose is deep enough to plunge into the depths of sexual depravity and she's willing to do anything to humiliate and ruin her. The danger only grows from there as yet another malevolent force is at work, one that goes well beyond threatening Amidahara and aims to bring about ruin to the entire world.