When I was growing up, we got a B&B tom cat - next door farm and he had been abused - even chip fat in his fur. Over three years, (seven cats inside), he slowly gained confidence to eat off a cat-dish in the window, then on the sill inside, then the kitchen sink and finally the floor. When my parents came to move, my parents asked the vet who said to take him as he had adopted us. He had a great last five years of his life, his fur recovering, and was just known as "Mogs".