I am very glad that it will be an option with futas. It is my hope that the main character is able to get a futa wife or girlfriend who enjoys taking it in the ass from him.
You're quite welcome, and for the record, I'm not doing a strictly submissive or dominant game, it's about the choices that shape relationships. So it is up to the players what kind of relationship they want to build with the characters in the game and also what these characters allow you to do with them.