Nair for Men hair removal lotion is the closest thing to useless I have seen in a body care product. That is my experience at least. This stuff really doesn't do a good job getting rid of the hair. Maybe if you have very fine thin hair on the area you are trying to get rid of it, but if you are tackling more coarse/thicker hair like that normally found on a healthy male, this stuff will maybe remove a 25% of it if you're lucky, and then you'll be left with some really weird looking spots. It's just plain messy and ineffective.
Honestly, just skip this product, go straight for the shaver or if you really want to get rid of it for a while, buck up and get your girlfriends waxing kit. If she can do it, you can.