We find in Section II of William Faulkner's short story "A Rose for Emily" that the only consistent companion in Emily's life is her black servant, Tobe. This is a symbol of Emily's (and maybe even Tobe's) inability to move forward from the past, since slavery had been abolished many years before the story begins.
...After her father's death she went out very little; after her sweetheart went away, people hardly saw her at all. [...] the only sign of life about the place was the Negro man--[...]t.
Tobe's character could actually be quite enigmatic. We know that the amount of time that he spent in Emily's company must have led him to know everything that was going on behind closed doors at the Grierson decaying estate.
And so she died[...] with only a doddering Negro man to wait on her. [...] we had long since given up trying to get any information from the Negro.
It seems to be quite evident that Tobe may have had a part on the plot to either lure Homer Barron back to Emily, to poison Homer, or to keep the body in the house. Maybe Tobe was an accessory to all three of the actions. After all, how could he not know what was going on, when he (Tobe) was the last person to admit Homer into the household? How could he not smell the decaying body like everybody else could? Moreover, why when he lets people in the house to pay their respects after Emily's death, does he take off and disappears for good?
Conclusively, aside from Homer's dead body, the only living companion that Emily has during her last years is her servant, Tobe. Yet, Tobe may have been more than just a servant; he may have very well been the only person who knew the secret of Emily's strange life.