I'm a Demon Lord. I Got Remarried to the Mother of a Hero, So She Became My Step-Daughter

Galtor Luzen, resident Demon Lord on the continent of Masgenia, falls head over heels for the Hero's mother. Once upon a time, a Demon Lord lost his wife and was all alone. But due to an unexpected turn of events, he met a woman he fell in love with at first sight. She happens to be..a Hero's mother?! (Source: Comikey)