Koutetsu no Majo Annerose

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.