Anal sex AFTER clean up

My guy and I have only had vaginal sex once, and that was the day we both lost our virginity. 

Now, we constantly have anal sex and while I love it just as much as him, he insists on never wearing a condom. Since he claims I can't get pregnant, which I know I can't with anal, unless something were to go up into my vagina. I still want to be on the safe side. So, when he cums in my back door, does anyone know of a way to clean out the inside instead of  just letting it sit there until it either A) falls out into my underwear and is sticky between my butt cheeks (which is disgusting and feels me with dread) or B) having to wait on the toilet until it all is out (which likely NEVER happens for me) 

Any ideas?