Episode list

Strategist Togame arrives on an island where she is supposed to find the head of the Yasuri family who was exiled there many years before and meets the current head of the family, Yasuri Shichika and his sister Nanami. Togame explains how she is on a journey to find the 12 most powerful swords in Japan that had been made by Shikizaki Kiki and needs his help. Seeing no reason to help her, Shichika refuses until Togame commands him to fall in love with her thus giving him a reason to help her. Suddenly attacked by a ninja from the Maniwa Ninja Corps with one of the 12 swords (Zettou Kanna), Shichika decides to help Togame and defeats the ninja. They then set out on their journey across Japan.

After a month of travelling, Togame and Shichika reach Inaba where their lead to the next sword (Zantou Namakura) is supposed to be found. The find that the swords current owner, Uneri Ginkaku, in a small room of his home and has nothing left except the sword and his home within the ever-growing sand of Inaba. After failed negotiations and learning Ginkaku's challenging speed, Togame and Shichika retreat from the home to form a plan. After some deliberation, they meet Ginkaku again and Shichika defeats him, earning them the second sword.

In their third month of travel, the duo wind up at the Sanzu shrine where the ex-bandit master Tsuruga Meisai protects the third sword (Sentou Tsurugi) and the shrine maidens who each carry one of the thousand blades classified as this sword. Togame is given the challenge of finding the original of the thousand swords before Shichika can fight Meisai for the swords. While Togame searches over the next few days, Shichika bonds with Meisai and learns or her struggles. Another ninja from the Maniwa Corps shows up and tried to wreak havoc but meets a quick death by Meisai's hand. the next day, Togame presents Meisai with what she concluded was the oldest sword and Meisai agrees to fight Shichika. The fight ends with Meisai's death and the third sword in Togame's hands.

During the fourth month, Togame and Shichika encounter Sabi Hakuhei, one of Japan's strongest swordsman who challenges Shichika to a duel for their swords. He proves to be much stronger than the other opponents Shichika faced before. Meanwhile, Shichika's sister, Nanami, is attacked by one of the Maniwa Ninja squads in an attempted kidnapping. Her foes soon discover that Nanami is actually the more powerful of the Yasuri siblings despite Shichika being the head of the family. She quickly deals with them as Shichika defeats Sabi Hakuhei, gaining their fourth sword (Hakutou Hari).

In their fifth month, the duo encounter the pirate Azekura Kanara who rules the small port of Satsuma and possesses one of the 12 swords (Zokutou Yoroi). Finding Togame resembles his deceased younger sister, he strikes a deal that if he wins a battle, he takes Togame as his woman. During the ensuing fight, Kanara proclaims his love for Togame and the fight then becomes more than just a fight for the swords. After finding the weak spot of Zokutou Yoroi, Shichika slams Kanara into the ground, forcing Kanara to admit defeat. Despite being one of the only survivors of Shichika's battles, Kanara spitefully changes the course of the ship Togame and Shichika take to get to their next destination.

Lost and freezing in the Ezo region, Togame and Shichika are found by an 11 year-old girl named Itezora Konayuki who is the last of the missing Itezora clan and takes them into her makeshift home. Later, she helps them find the sixth sword (Soutou Kanazuchi) and follows her clans instructions of not giving the word up unless defeated in battle. When Shichika challenges Konayuki and goes easy on her, his arm is broken and Konayuki becomes the first person to defeat Shichika. While Shichika recovers, Konayuki encounters the vengeful Maniwa Kyouken uses her power to take over the young girl's body and sees how Konayuki's clan had been annihilated by Nanami. She then engages Shichika in a fight. Unlike his last match with Konayuki, Shichika is able to see through this ninja's moves and defeats Kyouken's spirit, knocking Konayuki unconscious. Later, Konayuki gives up the sword and apologizes for lying to them about her clan's instructions. With Kanazuchi, Konayuki promises to take it to the mainland with her on her way to live at the Sanzu shrine.

Back on the island, Nanami becomes annoyed with her brother's slow progress and decides to set out and collect the swords herself. Along the way, she annihilates the Itezora clan along using methods much more violent and destructive than Togame and Shichika. She eventually comes to possess one of the 12 swords (Akutou Bita) and uses its power to strengthen her frail body by having it stabbed into her chest. Encountering his sister, Shichika fights his most deadly opponent during which Nanami asks him to kill her to spare her from the suffering that Bita brings with its power. After battling against Nanami's all-seeing eyes and inhuman strength and Togame's life being threatened, Shichika is finally able to free his sister from Bita by killing her.

In an abandoned lake, the duo find the next sword roaming around as a robot. Togame gathers information and attempts to capture the robot by setting traps for it, all of which fail. Shichika eventually fights the robot but it blocks and dodges all his attacks and surprises him with unusual attack patterns. Finally, the robot jumps into the air just as it runs out of energy, and Shichika swoops in to catch it, later sending the doll off to Princess Hitei.

Togame and Shichika now meet Kiguchi Zanki, owner of a dojo and the ninth sword (Outou Nokogiri). She and Shichika duel for Nokogiri but Shichika loses and Zanki decides to teach him the art of kendo. He proves to be very unskilled since his family's inheritance simply prevents him from wielding swords at all. This causes him to be clumsy and cause many accidents during their training to land them in positions that could be perceived as sexual without context to which Togame is victim to, making her immensely jealous. Meanwhile, Princess Hitei's servant Souda Emonzaemon is commanded to assassinate the Maniwa Ninja Corps, killing off one of their remaining members, Maniwa Umigame. Finally, Shichika and Zanki duel again even though Shichika is still horrible with a sword. Togame's newest scheme wins them the battle by distracting Zanki with shogi moves during the match, helping Shichika to win them the match.

Arriving in Togame's deserted homeland of Oushuu, the saint Higaki Rinne appears in front of Shichika in the form of a young girl whereas Togame sees him as her father who was murdered in front of her as a child. Rinne tells Togame that she can find the next sword (Seitou Hakari) 30 meters under the ground she was standing on and she starts to dig furiously for it. She passes out and Shichika questions her motives but she doesn't give him an answer, going back to work at finding the sword while Shichika is brought into Rinne's illusion world. Both Shichika and Togame are then forced to face the memories they didn't want to face . The two remaining Maniwa Ninja, Houou and Pengin head for Oushuu was well, anticipating that Emonzaemon would come after them. Emonzaemon is meanwhile receiving orders from Princess Hitei to find out who Togame really is. While Shichika and Rinne begin fighting, Rinne continuously guards, posing questions that make Shichika question himself and his motives. Frustrated, Shichika realized that fighting was pointless and runs back to Togame, remembering that his real reason for fighting was Togame all along. Woken from a tired slumber by Shichika, Togame realizes Rinne's intentions and is rewarded with the memory of her father's dying words. Later, the duo learn about Shikizaki Kiki from Rinne and find out that the Kyotoryu technique was actually Shikizaki Kiki's complete and final technique. Leaving with Hakari, they head for Owari but are stopped when they find Maniwa Pengin in critical condition, asking them to save Houou.