Shinkon Quest: Maou no Musume wa Majime Yuusha wo Duo to Shitai

Harold is a descendant of the brave hero who vanquished the evil Demon Lord. In these peaceful times, Harold has become just a common handyman. One day, the Book of God, which predicts the end of the world, is discovered. The condition to avoid destruction is... "The hero and the Demon Lord's daughter must complete the 'Marriage Quest'." Now begins the newlywed life with Yona, the daughter of the Demon Lord. While Harold is wary about the sudden marriage, Yona does all the household chores perfectly and gently pampers Harold when he is tired. However, she has a secret agenda… "So let's do it already ♡" (Source: Comic Regulus, translated)