Sounds like an american bully. Its sad that it becomes a fashion to get these dogs when many cant properly look after them. Even if the steel cage is outdoors it will get very hot in the hot season. The american bully usually has a good temperament against people. They are very powerful and need an outlet for their energy. https://www.dogbreedinfo.com/a/americanbully.htm He might be used for breeding, as they can rent him out to other people who has a female. If he is a good specimen. Tragic that he has to sit in a box.