Although Horace didn't intend it, at one point we see what happens when he uses his "cleaning" abilities on a human with the owner of the repo lot. It's revealed that it works by literally breaking down the items to the very atoms until they are nothing. This is reflected by the owner slowly disintegrating down to the muscle and down to the bone. And to top it all off, it finishes with the same "Done!" chime when a piece of trash is picked up.
Horace, at one point, is forcibly held hostage by the Man in Black, who is anticipating dismantling him. But first he forces Horace to watch as all his friends and family are on their knees, shot one by one to silence them. He witnesses the scientists from Germany and France get this treatment, and in the ensuing gunfight, Preston and Dr. Hiro are killed, Heather is fatally wounded and Sim is shot in the leg. And all Horace is able to do is watch...
