Matt Simon, a teenage basketball fan, is currently battling a "debilitating disease". Not that you'd know this, since he also just hit the free agent pool in NBA2K15, meaning anyone with the game can now have him go face-to-face with (or put him in the same lineup as) LeBron James.
As Bleacher Reports...reports, the game's developers, 2K, brought Simon into their offices, motion-captured him doing all sorts of basketball things and now, as you can see, he's in the game. That's a cool move on 2K's part; it would have been easier (and nobody would have noticed) if they'd just used a standard set of moves for him, but now Simon can say he really is in the game, right down to the way he moves around the court.
You can add him to any team's roster right now, provided you have the latest official update for the game.