Our neighbours cat has taken up residence in our house, we don't mind because he is friendly chap and doesn't cause any issues. He and our cat have got to the point of tolerating each other until about 5 minutes ago, in our garden he approached ours and swiped at her face, TVC chased him off but that is it now he is no longer welcome.
His owners have a kitten he doesn't get on with, 2 small children which he probably wants to be away from and they shut him out all day with no access to food, water or shelter so we feel a bit sorry for him which is why we are ok with him being around. Not any more.