character A is sick with a UTI. it's bad, and so their friend/partner character B has been taking care of them, helping them through it.
B lets A rest in their bed and goes out to run some errands, promising to be back soon. a very sick A is left behind.
quickly, the familiar need for the bathroom starts to crawl up on them- and it hurts. perhaps they even start to cry, depending on the character. it burns, and the more they hold it in, the worse it gets- but they're too ill to get up.
they curl in on themselves and their eyes are brimming with tears. all they want is some relief- so... after a few more moments of pain, unable to think even straight, they push. hard.
they force out in big, big spurts what feels like gallons of urine, a warm wetness quickly spreading across their butt and across the sheets. their pajama pants are growing soaked- but they don't care. it feels so good.
the stream comes to a stop, and they take a moment to come to their senses, laying in a puddle of their own mess. they eventually realize the extent of what they've done, and their face flushes red as they let out an embarrassed sob.
they wet B's bed on purpose.
disgusted with themselves, they lay there, wallowing in their self depreciation until B comes home. B heads upstairs to check on them, only to find them quietly crying to themselves. they rush over, gently asking what happened, and A has to explain the situation.