Whenever I am driving on a long trip or in a situation where my friends or family members have to desperately use the bathroom but will not be able to reach the restroom for several minutes, I like to tickle them or press on their stomach. I personally consider this a prank, although some may just consider this a bastardly act.
Saying to me, “You better pull over at the next exit. I have to use the restroom pretty bad.” is about the worst thing you could do to yourself if you are traveling with me. You just let me know it is time to press on your stomach and make you feel even more uncomfortable. I will keep attempting to press their stomach or use the car’s brake in a jolty motion until they get a little irate and then lay off. Although it has been threatened many a time, fortunately no one has yet urinated on my passenger side seat.
Another torture device that you can use in this situation is the power of suggestion. “So, you have to go pretty bad do you? Wouldn’t it feel so good to relieve yourself right now. Too bad we are so far away from a restroom. You think you can make it?” Keep talking to them reminding them of their discomfort so their mind won’t let them relax. This tactic is just like when someone gets a mosquito bite and you ask them if it itches. Probably not until you said something forcing them to think about their insect bite.