Jiryuu Sendou is the leader of the Sendou clan.
Light Novel debut: Naruto Jinraiden: The Day the Wolf Howled
Jiryuu formed the Sendou clan after the Howling Wolf Village declared its neutrality from all conflicts. He gathered together many of the village's former shinobi - left unemployed by the neutrality - and created a criminal gang that primarily dealt in saigenzai, a popular hallucinogen. Because of their saigenzai's poor quality, Jiryuu wanted to learn how to make the special Kotarou sold by the Kodon clan. He and his clan would periodically harass Reishi and Kina Kodon to try and force them to turn over the secret to Kotarou. Itachi Uchiha, while visiting Reishi and Kina, would fend them off.
(Source: Narutopedia)
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