As a close friend who had shared so much youthful passion with him, Guy was the first to sense something unusual about Kakashi. Compared to before, there was foreign chakra in Kakashi's body, something that usually only happened after a ninjutsu attack.
But Guy soon realized Kakashi wasn't injured, so he gave him a puzzled look.
The others reacted much the same way, but Oto Uchiha frowned, activated her Sharingan, and studied him for a moment. "That's natural energy. Kakashi, have you been training in Senjutsu? It's a miracle you're still alive with that much natural energy in you."
Kakashi nodded and rolled up his sleeve, revealing the toad-like features on his skin. He smiled and said, "I didn't expect you to notice. I've been studying Senjutsu at Mount Myōboku with Lord Jiraiya lately..."
Guy stepped forward and patted Kakashi's shoulder, muttering, "No wonder I couldn't find you for a spar. Your strength must have shot up after learning Senjutsu. Let's have another match."
Kakashi immediately looked awkward, standing motionless with a dead-eyed stare.
"Don't tell me you haven't learned it, Kakashi? But you're a genius..." Guy muttered again.
All Kakashi could hear in Guy's words was mockery. The word "genius" grated on his ears.
Although he had become a Jonin at twelve, his strength had stagnated ever since. In other words, he had more or less reached his own limits.
Aside from years of effort, the only way to break through those limits was a kekkei genkai. But with only one three-tomoe Sharingan, he couldn't awaken the Mangekyō Sharingan like Oto and Shisui.
At that moment, Oto withdrew her gaze from Kakashi and casually said, "Kakashi, do you need that natural energy cleared out? It's dangerous to leave it in your body."
Kakashi gave Oto a surprised look and