Set in Kyoto, Japan in 1863. Koto Nakazawa learned from her father Emon Mago "Hoshinryu" which is a Japanese fencing school of thought. She leaves her hometown to become stronger. Koto Nakazawa and her older Sadamasa take part in "Roshigumi" led by Hachiro Kiyokawa.
One day, she stops outlaws who threaten merchants. When she is about to use her sword, Ryoma Sakamoto stops her.