Tobe is also very loyal. He is black, so probably he is descended from the slave families that Miss Emily's family most definitely owned when she was younger and the family was more affluent. This is one reason why the town looked down its nose at Tobe being in the home alone with Miss Emily. There were rules of social acceptance, and it would have been much more acceptable for Emily to have a female companion/servant than a male of any race.
Tobe was Miss Emily's man-servant. By the town's standards, he was not an appropriate choice to stay in the house alone with Miss Emily, or to do a very good job of keeping the house up. Tobe was Miss Emily's only "friend". Tobe does not speak to many people in the town. He is also the only person to be with her when she dies.
After Miss Emily dies, he lets people into the house, walks out, and is never seen again.