Aboard a ship connecting Kyoto and Osaka, Osan was pickpocketed by a sham blind biwa player. A man who looked like a merchant retrieved the wallet for her. Osan was a woman being sold off for the sake of her yakuza-like brother, Nin'kichi. The man in the guise of a merchant turned out to be the Rat Thief, Jirokichi, the infamous thief of Edo. Due to this chance encounter, the two ended up staying at the same hot spring inn. However, one morning, as Jirokichi was about to leave alone, Osan, with the intuition of a smitten woman, confessed she knew he was the famed Rat Thief.
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