Chihiro Rokuhira, a quiet young man who grew up training to follow in the footsteps of his father, spends his days learning the craft of swordsmithing in a world where modern landscapes converge with timeless Japanese aesthetics. His father, Kunishige Rokuhira, is a legendary and unparalleled master smith, the sole creator of six Enchanted Blades of immense power, weapons said to have ended a great war and capable of shaping the fate of the entire nation.

Their peaceful and warm daily life is brutally shattered when a mysterious and powerful organization of criminal sorcerers known as the Hishaku attacks. In this assault, Kunishige is murdered, and the six legendary Enchanted Blades are stolen. Left alone in a world suddenly engulfed in darkness, Chihiro is consumed by a vow of revenge. He takes up the seventh Enchanted Blade, Enten, which his father secretly forged and left behind, and embarks on a blood-soaked path to reclaim the six stolen blades and exact retribution on the Hishaku.

Armed with Enten, which is visually represented by three ethereal goldfish named Aka, Kuro, and Nishiki, Chihiro wields a unique sorcery that allows him to manifest the blade's power. He is not entirely alone in his quest. He is joined by Togo Shiba, a veteran sorcerer and an old friend of the Rokuhira family who formerly belonged to the Kamunabi, the national sorcerer organization. Despite his easygoing personality, Shiba possesses formidable abilities and supports Chihiro by gathering information. They are assisted by Hinao, a young woman who works as an intermediary for sorcerers at a cafe called Cafe Haru Haru, and Char Kyonagi, a bright and kind-hearted girl who is the last survivor of a clan with astonishing regenerative abilities, making her a target for those seeking to exploit her power.

As Chihiro hunts for the stolen blades, he comes into direct conflict with Genichi Sojo, a ruthless and inhumane weapons dealer who operates in the underworld and has become the contractor of Cloud Gouger, one of the stolen Enchanted Blades. Sojo harbors an intense and twisted fixation on Kunishige Rokihira. This leads to the first major confrontation in the Versus Sojo Arc, where Chihiro must face a foe wielding his father's craftsmanship for evil purposes while also protecting Char from Sojo's clutches.

Following this conflict, Chihiro finds his path intersecting with the Kamunabi, the government-sanctioned sorcerer organization. While the Kamunabi seek to collect all Enchanted Blades to maintain peace, placing both Chihiro and the Hishaku on their list of targets, their interests become temporarily aligned. The Hishaku begin to move more aggressively, forcing Chihiro to form an uneasy alliance with the Kamunabi during the subsequent Rakuzaichi arc and leading into the Enchanted Blade Bearer Assassination Arc. This arc begins when the Hishaku launch an attack on one of the original contractors of the Enchanted Blades, Yoji Uruha, who wields the Kumeyuri blade. Uruha, who had been entrusted with the blade eighteen years prior, is revealed to have been deeply fond of Chihiro's father. Chihiro and his allies must now team up with the Kamunabi to protect the surviving sword bearers from the Hishaku's assassins. The story unfolds as a shonen action narrative teeming with political conspiracies, underground warfare, shocking betrayals, and a determined protagonist who carries a belief as strong as forged steel in his heart.

The television anime adaptation, produced by the animation studio Cypic and directed by Tetsuya Takeuchi, features character designs by Keigo Sasaki and stars Taihi Kimura as the voice of Chihiro Rokuhira.