Most men play down how much they want it though, so just turn up with the necessary plastic appendage already on. I'm sure he'll appreciate the surprise.
It is when you look into her eyes, and see someone you love and respect beneath you, looking back at you with love. That, my lady friend, is what makes the night memorable.
But I will say, if that does not work, do try the best friend thing. 90% of the time it works every single time.