It will take several treatments plus it depends too on her hair color. Make sure they get it all.
Hopefully she'll have a few follow up sessions to catch any hair that spurs though.
She'll love it as it will gave her soooo much maintenance time in the morning.
You'll both love it as her bald pussy will taste great and she'll really feel yours and others man's tongue
When done a picture would be great...either here or on my profile