This could be fun

[Peevert]

Watching your passenger use one of these:

http://www.luuux.com/viz/car-toilet-...-pee-in-ur-car

[Dusty Harold]

It seems to me a little bulky to use . plus the point that the girl made about what others might think / being observed peeing into this device
while still sitting in the car . With your pants and underwear pulled down Might prove a little awkward if not embarrassing for a young woman to use . Especially if there are any male passengers sitting right beside her . When she is peeing into it