He could use them for so much more than any of us could. We'd just use them to kill pain; he could use them for genuine enjoyment.
Madness string 18093
There's no way to know. The event horizon hides everything from us. The matter in a black hole could be just barely smaller than the horizon and we'd never know. It could be emissive, but any glow just falls back in. We just don't know.