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Fu-ha Jin is a strange looking ninja first appearing Ryuuko no Ken Gaiden (Art of Fighting 3). He was a disciple of the Kisaragi school of ninjutsu until he was passed over for Kisaragi Eiji as the sole successor to be leader. Jin left in anger and decided to wait for his opportunity to destroy Eiji, and at the same time decided to fight Eiji's rival Ryou Sakazaki.
He had little notability until re-discovered by Japanese website Bohyou, which led to the Japanese MUGEN community finding him and frequently using him. His odd looking moves and memetic lines led to his popularity as a joke character.
This, in turn, has led him to appear in MUGEN related works such as Touhou - The Iron of Yin and Yang, where he is the only non-Touhou, non-Final Fantasy XI character.
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