[On the surface, Forensics seems like a strange choice of class for Rudy Cooper, but of course he's only here to support his roommate's efforts. Of course.
He's already got a pair of latex gloves on-- he's well-prepared for this exercise-- and walks carefully onto the staged scene, eyes on the floor as he moves, trying to avoid disturbing any evidence that might be there. He pays little attention to the blood, instead stooping to look critically at the "victim." Only after that does he look at the surroundings.
Mostly, as the class continues, he keeps to himself-- quiet and intent, not taking notes but listening keenly both to Dexter and to his fellow students.]