Being stuck in the car, desperate to pee, is not a terribly uncommon situation. This is exactly the predicament we find Sosha in at the start of this video. She is driving down a narrow road, no place to pull over, and clearly desperate to pee. It is obvious she is on the verge of loosing control and wetting in the car.
At the last possible moment, as she is starting to dribble in her jeans, she spots a small side road and pulls off. She springs out of the car, but it is too late. Unable to hold back the flood any longer, she soaks her jeans.
Ashamed at having an accident, she tries to hide behind her car, out of the view of passing motorists, as she cleans up. Carefully, she removes her soaking wet jeans. Luckily, she just happens to have clean, dry pants along in the car to change into.