Hideyoshino, an ordinary girl with a knack for trouble, stumbles upon a mystical scene at a local shrine while seeking academic success. A chance mishap catapults her back in time to the Sengoku Era after disrupting a stranger's magical ritual. In this altered reality where all are female, Hideyoshino partners with Oda Nobunaga and Akechi Mitsuhide, aiming to locate the legendary Crimson Armor capable of unifying Japan under its bearer's rule.