Dirty bbw

I have a fantasy where a big lady with a big ass goes to the loo but is too big to even wipe her own ass. She makes it back to the bed and lowers her ass to my face for me to clean her , this I willingly do and making me really horny in the process and wanting to stick my cock in her dirty ass and get her all messy. Then we get in the the shower where I'm very attentive in cleaning her folds and flaps .