If you want anal, you start doing that to a woman from the very start. Make her understand that’s how you have sex with her. Then it becomes what she expects… her reality.
This is the way you fuck a woman. She’s clearly well trained and used to being sodomised. She’s more valuable as a woman… her anus is just another hole to be used for pleasure now, and is nice and loose, like her pussy. She’s been turned into a fuck toy with 3 holes. Perfect.