During the Sengoku period, Yoshiharu Sagara, a high schooler, gets thrust into a battle and is rescued by the legendary Hideyoshi Toyotomi, who perishes shortly after. The dying warrior requests that Yoshiharu take his place and be the next feudal lord. Determined to maintain the timeline, Yoshiharu sets out on a journey. However, as he helps Nobuna Oda - the female equivalent of Nobunaga Oda - Yoshiharu realizes he's in a different world where warlords are charming young girls. Yoshiharu decides his best bet at returning home and correcting the timeline is by accompanying Nobuna and becoming her retainer, all the while utilizing his knowledge of the "Nobunaga's Ambition" video game to alter the war's course. Yoshiharu's goal is to help Nobuna conquer Japan and win over every woman's heart.