Even fatigued, Yamato couldn't help but notice the subtle play of emotions across Kakashi's face and the through the tone of his voice. Yes, the man sounded tired, but there was a fondness there that he hadn't heard in a very long time and it was being directed at students no less. It was enough to get Yamato's full attention and his harried, vacant look, turned into a suspiciously warm smile.

"If I didn't know better, Kakashi-senpai, I'd be inclined to think that you're enjoying playing Sensei. That doesn't sound much like a punishment.."

Whatever Obito had been thinking, had clearly backfired or something had truly changed, either way, Yamato begrudgingly set aside his envy and indulged Kakashi's lucky break with the required amount of teasing.