That guy is so obviously gay...I guess there are no straight professional tit painters. :-( I'll be the pioneer here.

Girl: "Eew, what are you doing?"
Me: "Um...I have to...lick your ti-I mean nipple to um...make the paint stick."
Girl: "Oh, okay. As long as you aren't some pervert trying to get free tastes."
Me: "No worries dear [trying hard to hold back my evil laughter]."