Helck manga volume 1 features story and art by Nanaki Nanao.

Three months have passed since the demon lord was struck down, and the Demon Realm is holding a tournament to select his replacement. The leading contestant is Helck, a human hero who claims to hate his own kind. Some aren’t happy with the idea of a human becoming the next demon lord - especially Vermilio the Red. She wants nothing more than to protect demonkind and prove Helck to be their enemy, even if she has to rig the competition to do it!