In case he lost control of himself. Gregory had written it, and Draco still felt as if this meeting were, if not a good idea, at least something that must happen - he had crimes of his own to pay for, after all, and Gregory and Vincent and, yes, even Theodore were some of the worst among them.
Then again, Goyle knew something of him that the world at large did not know, and that made Gregory dangerous even without the notice that he was likely to lose control. Draco wondered at what form any of that would take, and decided that it was far better that it happen in his own home than somewhere in public, just in case.
At the knock, Draco reconsidered for only a moment, but then went to answer it. Himself, even. There was one house elf in the flat, just one, but she was not allowed to answer the door - in case one of the muggles wandered up.
"Goyle," Draco, dressed in simple slacks and a black shirt, looked him over and felt, again, what was owed, but what he felt did not show at all in his features as he stepped back to let the other man enter.
The flat was, of course, as posh as the building it was in - large and decorated in brass and leather, green and rich browns across the walls.