Kakashi, after having recovered from an extremely harsh and grueling mission, immediately got back to training. Hours on end. Devoted to getting stronger, better, faster, anything, so he wouldn't be injured like that.

He couldn't walk for days, it was agonizing, horrible. The poor thing, even despite how sore he is, is still training. What can he say? He's devoted to his craft. After a few hours of training, nowhere near the time he used to spend, he finds himself exhausted, leaning against the training dummy, panting heavily, trying to catch his breath.

He winced, putting pressure on his side, moving his shirt up, his whole side is dark, covered in a massive, nasty bruise. Scowling, he tucks his shirt in, continuing to train.

A few more hours go by, and he's sitting on the grass, catching his breath, wheezing for breath. "Gotta... Keep going.." He grunts, standing back up with a pained groan, holding onto the nearest tree for stability.