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) — Description from AniList community (anilist.co).