Furin Yuusha ~Sono Furin ga, Sekai o Sukuu~ The Motion Anime

 

The main character, who had long dreamed of reincarnation in another world, one day dies saving someone.

The main character ends up in heaven and is happy to have reincarnated in the world of his dreams, but he is given a mission to become a "hero-adulterer" who saves the world through "adultery".

The main character reincarnates, thinking that cheating is bad, but in the new world he meets married women who don't know what to do with their lust...