Sometimes, when Tsuna pauses in his work, he'll glance absently at his hands. His eyes never linger. Only for a second, he'll stop and compare them to their appearance many years ago. He'll gaze at the fresh manicure that Reborn insisted on and then find it incredibly odd to see such well-maintained nails next to such scarred and calloused knuckles. He takes a second to wonder what they'd look like had they not been blackened by the guilt and anger that he deals with so frequently.
He never stares too long.
Oddly enough, it has nothing to do with the knowledge that the more time he wastes, the more his work builds up. It has everything to do with the way his memory recalls them coated in red.