An ex-convict, released from prison at the beginning of the story, who seeks out apprenticeship under the legendary Eighth Generation Yakumo Yuurakutei, who performed in Kyouji's prison. He is taken in as Yakumo's first ever student, and is given the name Yotarou (rakugo slang for "fool").

After ten years of training under Yakumo, he is promoted the rank of shin'uchi. To celebrate, he shaves his head and takes on the title of the Third Generation Sukeroku Yuurakutei.
He gets married to Konatsu a few years after Shinnosuke is born. Together they have a daughter, Koyuki.

Sixteen years after his master's death, he becomes the Ninth Generation Yakumo Yuurakutei.