When you hide your keys in your pants, and your boyfriend has to fish them out. (Typically while drunk)
Matt mustang ruddered Billy to get home, and get off.
The act of storing your Ford Mustang keys in your crotch, so that your boyfriend must fish them out to drive your diva ass home
Matt was at a car show and his boyfriend had to mustang rudder his keys to get home. Everyone came home a winner.