Mouthwash on not in. Mouthwash is safe for the delicate oral tissue its not going to hurt your ass on the outside. I was searching for something other than isopropyl alchohol since that burns like fire when washing up prior to play.
I'm such a germphobe so i got creative
I think 90+% IPA would be v.stingy or worse. How about vodka? Which is usually 40% or 50% ethanol. Dampen a clump of TP and gently rub; repeat until TP colourless. Doctors use surgical spirit for de-germing skin before an injection; SS is denatured ethanol 90% ish. Cheap to buy from pharmacy but perhaps too strong for a anus.