The Primal realm was, largely, considered the territory of the Primal race. That went without saying. That did not, however, stop Death from living there, nor did it prevent him from using it as his base of operations.
Unlike his counterparts, he had never hidden himself. He had always remained out in the open, unafraid of any action or retaliation. Of course, due to the restrictions from the universe, he hardly ever left his humble home which acted as a kind of isolation and protective barrier from him.
As long as his main body remained within, the universe would do nothing to him. Any clones he sent out would have to be restricted to the Dao Lord realm, but that was also true of the others, so he didn't mind it too much.
