A sexual move often performed by gymnasts or dancers. It involves both partners in the Standing 69 position usually with the lighter partner backwards. The standing partner proceeds with cartwheels until he or she hits an obstacle. This often results with both partners simultaneously tightening their jaws on the recieving partners genitals, which ultimately leads to severed genitals and/or severe cuts.
I did a Standing 69 Cartwheel with Kalee and she ended up biting my cock off when we ran into a wall. In return, I bit her clitoris off.