Head Spinner

He stands on his head with his legs in the splits while you wrap yourself around his torso, scissor between his legs and balance in his armpit.

Why It's Impossible: Look ma, no hands! Or not. There are so many logistical issues here. Starting with: you may be dating a professional break dancer, and he may be able to do some electric bugaloo bullshit, but he can't balance hands-free and pump his upside-down dick in you while you're balancing in his armpit. There's this thing, you see, it's called gravity.