Patreon doesn't allow rape unfortunately, otherwise the game would already have content of the girls raping you. Like, Patreon allows blackmail rape, but not force rape or sleep rape for whatever reason.
That aside...You can allow Kate to get in a relationship with Rick and THEN steal her from him. I promise you, it's delicious. There is also Verana, the mother of Arianna; Her relationship is the rocks with her husband so you can eventually trick Roderick into letting you help him just so that you can swoop in and steal Veranna from him.
The mayor's wife is more of a Penny dealio, since the mayor is an implied dick from the get go, but she is there.
I don't know if you count widows whose husbands die over the course of the game, but there is the chieftain's wife in Rumah. She clearly loves her husband and you can woo her after he bites it.