Kyo is an artificial construct, being born of Kyoshiro's attempt to purge violence and cruelty from himself: Kyo is the dark half of Kyoshiro's soul in a Mibu-made homunculus.Kyo meets Migeira, a strange man from Europe who explains that Kyo's sword, a Muramasa blade, has special powers. Yukimura convinces Kyo to enroll in the Shogun's tournament, where all the greatest fighters in japan are gathering. During the battle, the truth of what happened is revealed and Kyo saves Mahiro from their common enemy. Mahiro accuses Kyo for killing her sister, and attempts to take her revenge. He meets the charismatic samurai Yukimura Sanada at an in, and they are later attacked by a mysterious ninja girl, Mahiro. The warlike Kyo has now completely taken over Kyoshiro's body. This new opponent is too strong, and Kyoshiro is forced to call upon the Demon Eyes Kyo's power. Shirogarasu, the last remaining assassin, comes to challenge both Kyoshiro and Benitora. Benitora, another one of the gang changes sides to save him.

One of them challenges Kyoshiro, thinking he is Demon Eyes Kyo. It turns out that the samurai village is being terrorized by a gang of hired assassins. But the strange women Kyoshiro met earlier is only interested in Demon Eyes Kyo. As they stay at a village, some people want Kyoshiro dead. Later on during the night, the two met a strange women. However when he finally gets to Yuya, Kyoshiro regains control of his body. Kyo returns and vows that nothing will stand in his way, not even Kenyou or a Samurai. The demon beats up Kyoshiro, but Kyo takes over his body. The demon was actually a guy who fought in the war four years ago. Then four years later, Kyoshiro meets Yuya Shiina and then a demon attacks them. The two stay on the battlefield until a explosion happens. As Yukimura, Sasuke and Saizo run as Yukimura calls out to Kyoshiro but to no avail. Then, Yukimura comes and tells them to stop because Sakuya creates a meteor raining down on the battle field. Meanwhile, Kyo destroys Kyoshire's sword and tells him that he lost and should give up. During a violent war Demon Eyes Kyo and Kyoshiro Mibu battle each other while Yukimura Sanada, Sasuke Sarutobi, and Saizo Kirigakure arrive at the battle ground where Kyo and Kyoshiro continuing fighting.

Samurai deeper kyo muramasa