When do you consider your ass clean?

I'm sorry if this is a little bit unhinged... But I need to know when do you consider your ass clean when douching because I can't find a routine that would satisfy me.

I douche like 10-15 times per session and everything usually seems to be alright - water comes out clean and all but then I like to "test" my butt before any action and I finger myself first. I feel like there's always some smell left on my fingers and I hate it.

I know it's ass and it's not gonna smell like flowers but I wonder if there's a stage where the smell is gonna be just neutral? Should I keep going and douche more? It gives me anxiety I dont want my partners dick to smell...