Guide dog

[rebbonk]

There's a blind guy waiting at the traffic lights, when his guide dog suddenly pees on his leg.

The blind man reaches into his pocket for a dog-biscuit, which he then gives the guide dog.

Another man standing nearby sees this, and says to the blind man, "I think that's wonderful - the dog peed on your leg, but you still gave him a biscuit."

Spoiler:

"Yeah, well I was just trying to find where his mouth is so I can kick him in the nuts!"