Absolutely on the cross contamination. First off, I will not be doing a thing you are not willing to do for me, and I KNOW you are not going to lick my behind. And just like you do not suppose to perform anal before vaginal, the same would go for oral. Lastly, it is called K.Y... USE IT! Do not spit on people unless that is their kink. Old spit even 5 minutes out of your mouth, funks up like light morning breath.