Despite it being her high-school debut, Tora Takei is struggling to fit in among her peers. Suddenly, she finds herself transported back in time to the Warring States period. In order to return to her own time, she must alter history. In a classic disguise as a man, Tora becomes entangled with Mori Ranmaru, the handsome and lethal guard of Oda Nobunaga. Over time, she discovers Ranmaru's genuine and virtuous nature, and inevitably falls in love with him. This is the story of Tora's journey through time and into the heart of the Warring States period.