If you find 2 girls who work together normally then they tend not to expect any washing except for a condom change.
If you book to independents and then get someone who is gay for pay. Really anything can happen.
I've had experiences of girls using wet wipes on me between giving oral. To girls who are so busy kissing every hole that washing inbetween never even came up.
It's hard to find the perfect duo at the end of the day though, expect it to not live up to your expectations
Sorry to be a spoilsport.