How much do you love her?
Actually, I would guess-that if she's an experienced lady you might mention how good you are making a lady cum with your talented tongue and how much better it feels to your lady, who have had a clean shaven tush. There is quite a difference and it's worth the maintenance. I'd do anything to keep my man satisfied...and perhaps she feels the same way.
Do pay attention to the words you choose to use to mention this. Some of us absolutely love dirty talk and others don't. Or offer to shave her and together you will have a very hot time and ample reward for the gesture. Have fun, be sweet.