Sengoku Strays

Sengoku Strays (戦國ストレイズ) is a manga series by Shingo Nanami. It was serialized in Gangan Joker.

Plot
Kasane is your average kendo-obsessed girl, when a brush with a mysterious sword sends her back in time to the Sengoku Era. Stuck in an unfamiliar time and place, Kasane also has the poor luck of winding up right in the middle of the turmoil that surrounded Oda Nobunaga's rise to power!