A month later.
Karin stayed with Tsunade, while Uchiha Sora returned to Kusagakure.
Before leaving, he left a mark on Karin, just in case.
Although Karin was reluctant to part with him, Tsunade was very fond of her and intended to teach her all of her Medical Ninjutsu.
Wanting to help Uchiha Sora in the future, Karin gladly agreed.
Although Uchiha Sora had learned all of Tsunade's Ninjutsu, he had not acquired her vast medical knowledge.
Medical knowledge and Medical Ninjutsu were different: one was the theoretical foundation for treating illness and saving lives, while the other was the means of providing treatment.
Uchiha Sora had learned only the means, without the foundation.
So while he could probably heal external injuries, helping others with complicated, hard-to-treat illnesses would be much more difficult.
By staying with Tsunade, Karin would learn not only Medical Ninjutsu, but also that vast, complex body of medical knowledge.
After returning to Kusagakure, Uchiha Sora began steadily accumulating chakra, concentrating it in the Diamond Mark on his forehead.
To his disappointment, however, Katsuyu refused to let him enter the sacred grounds of Shikkotsu Forest, claiming that the Uchiha Clan had no aptitude for Senjutsu.
Yet Uchiha Sora could clearly hear a trace of hostility in Katsuyu's voice.
That hostility seemed to be directed at the Uchiha Clan.
It seemed he would have no chance to study Senjutsu in Shikkotsu Forest for now. He could only try Ryūchi Cave or Mount Myōboku next time.
"Leader! A message has arrived from Konoha! Please take a look!" Pakura appeared before Uchiha Sora and respectfully handed him a letter.
Uchiha Sora opened it. The Third Hokage had written to invite him to negotiations at Ancient Kikyo Castle on Konoha's border.
"Heh, has that old fox, the Third Hokage, finally lost his