There's a Big Issue seller who has a pitch in the afternoons outside Angel Tube station.
A while ago, he found a stray cat with a badly bust up leg, so being a kindly soul, he took the cat along to an animal shelter to get it sorted out. He wasn't expecting them to tell him when the cat was healed, he was to take the cat back with him - but that's what they said and that's what happened.
The cat became incredibly attatched to its rescuer and would try to follow the man whenever he went out. Realising that cats do what they want, the man gave up trying to get the cat to stay home and allowed it to come with him and these days the cat will be sat outside the station as the man sells copies of the magazine, calmly guarding the takings and posing for photos.