In the Infinite Tsukuyomi, Sai was happy. He was able to express that happiness through his smile. Everyone said that his smile was the greatest in the Hidden Leaf Village and was able to connect people with it. Even Naruto boasted it.
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In real life, Sai was tied to the Shinju Tree along with everyone else. Naruto wasn't there to save them. Oh, well. Sai will come to learn how to express himself once he becomes a White Zetsu soldier. Kaguya-hime would make sure of that once she drains him dry.
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In the first month, Sai's clothes disappeared first. His cocoon kept him warm and he didn't notice a thing.
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Sai's chakra was being drained as the months went by. His art jutsus were gone in no time.
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Years passed, and Sai's body was starting to show certain changes, although there weren't that much to begin with. His hair color was starting to fade and his normally black eyes that reflected the Rinnegan had changed yellow. In fact, the only thing that hadn't changed was his pale skin.
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Another year passed and Sai's jutsu were entirely gone. No longer would he be able to paint and give life to his creations again. Literally.
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Another year passed and Sai's body began to be drained as well as his chakra. His bones poked through his skin, his muscles began to recede and his eyes were beginning to be sucked into his sockets. Yet he wasn't dying, but being preserved so that he can be rebuilt.
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Another year passed and Sai's self was being erased. He started to lose touch of who he was. But something else was taking place in who he is, words of a female telling him to accept his position and his place as a soldier. Only then will he no longer stand out like he did. Sai listened and obeyed like a proper soldier.
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In no time, what was left of Sai was nothing more than a dried up husk with no trace of him whatsoever. Now the cocoon can begin the next process and started to fuse to his skin.
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A year passed and the cocoon started to become like a second skin. The facial features were pressed to the point that one could see the outlines of a nose, eyes and a mouth. Soon, the arms were tightly bound as well as the legs.
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Another year passed and soon, the bound body started to become more outlined and features such as the toes and fingers were wrapped as well.
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Sai was gone, and in his place was White Zetsu. A soldier loyal to Kaguya-hime. But he didn't care anymore. Before he became a soldier, he stuck out like a sore thumb due to his awkwardness. Now he didn't have to worry about that anymore. Everyone was the same as him, just as it should be. Now he and his fellow soldiers needed to ready themselves for the coming war with the two interlopers.
