The Audacious Fellow
Koyanagi saved a woman from throwing herself along with her child in the water. They were the wife and child of Matahachi of Shishidome who was arrested by Koyanagi. Koyanagi was frustrated that he couldn't catch Monzaburo of Amabata and lets Matahachi out with his family in exchange for information on Monzaburo's whereabouts.
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