Saikyou Maou wa Musou shiteta noni ~Nyotaika Kaijo no Kagi wa Hitodasuke no Tabi deshita~Saikyou Maou wa Musou Shiteta no ni ~Nyotaika Kaijo no Kagi wa Hitodasuke no Tabi deshita~; 最強魔王は無双してたのに～女体化解除のカギは人助けの旅でした～; The Strongest Demon Lord was Unstoppable Before: The Key to Return to Being a Man Lies in a Journey of Helping People

Dinato, once feared as the mightiest Demon King, was cursed by an item belonging to Annie, the female hero he defeated. Transformed into the body of a beautiful girl, Dinato's troubles only grew when Annie was revived as a gyaruand due to the curse, Dinato is unable to defy her! Stripped of most of his powers and now targeted by his former monstrous minions, Dinato is brought to his knees by this harsh reality. Amidst his struggles, Annie reveals the only way to return to his original form: a journey of "helping people" by defeating monsters that threaten humanitya task utterly unbecoming of a Demon King