Shin Uchiha knew full well that Kirigakure and Konoha had a long-standing feud. Just take the Seven Ninja Swordsmen of the Mist's raid on Konoha: Might Guy's father, the eternal Genin Might Duy, had kicked those seven Calabash Brothers down to three Musketeers. That was quite a feat.
Moreover, after unleashing that burst of power, Might Duy had died on the spot from the side effects of the Eight Gates Released Formation.
Of course, the grudges between Konoha and Kirigakure went far beyond that. Ao of Kirigakure's Byakugan, the Three-Tails being sealed inside Rin Nohara, and other incidents all stood as reminders of the irreconcilable hatred and conflict between the two villages.
That was why Shin Uchiha found it so baffling that Kirigakure would participate in the Chunin Ninja Exams hosted by Konoha.
Of course, even if Shin Uchiha scratched his head raw, he would never have guessed that Tsunade and Mei Terumi had learned of each other's intimate relationship with Shin. Without needing to say a word, the two had decided to use this opportunity to face off and see just how strong the other village's Kage—the woman their beloved man was also involved with—really was.
Shin Uchiha rubbed his chin in frustration, then gave up thinking about it. After brushing his hand over Izumi's and Ye's cheeks, he used Takamagahara and followed the space mark he had left behind, returning to the Hokage Office along a familiar route and leaving a trail of smug laughter in the space behind him.
When Shin Uchiha arrived at the Hokage Office, he was just about to greet Tsunade and Shizune when he suddenly heard a familiar voice making a racket. This unexpected scene stopped him in his tracks. Raising an eyebrow in interest, he stood quietly in a corner and looked