Inside Yanbai's backend space, which also counted as his Dōjutsu Space.
Here, Yanbai had not accelerated the flow of time relative to the real Shinobi World. However much time passed for Madara Uchiha outside, the same amount passed for Yanbai here.
Every day, apart from studying in the backend, Yanbai wrote system evaluations and... chatted with Black Zetsu.
At that moment, a partially manifested screen floated before Yanbai, and his hands tapped out a peculiar melody on it.
Black Zetsu sat beside Yanbai and murmured, "Little brother, I've seen plenty of versions of Madara in this endlessly looping Shinobi World. This version really has had it rough. How about... taking him with you when this round ends?"
Yanbai's hands paused. He stiffly turned toward Black Zetsu and said, looking thoroughly exasperated, "Another one? This is already the third version of Madara, you know?"
Black Zetsu muttered, "Sure, you're familiar with three different versions of Madara Uchiha, but they're all different Madara Uchihas. Their lives were completely different, after all. They only look alike and all came from the Uchiha Clan during the Shinobi World's Warring States period. They're really no longer the same person. Although the last Madara might have stabbed himself for you, too. If you hadn't always deliberately made him angry, he would have received your 'Gift' long ago..."
"Zetsu, please stop..." Yanbai looked helplessly at Black Zetsu. Afraid he would keep talking, Yanbai hastily changed the subject. "Tell me what's happening outside now."
"Tobirama came looking for him after all. Madara gave Tobirama all those Impure World Reincarnation techniques you left behind." Black Zetsu said cautiously, "Little brother, Madara erased some of the notes you wrote on the Impure World Reincarnation Jutsu."
At that, Yanbai looked at Black Zetsu in bewilderment.
Black Zetsu hurriedly explained, "You wrote,