Sesshomaru turns his attention to Kagome, gliding over to her in one quick move. Inu Yasha tells her to give the sword to Sesshomaru, but she refuses. Sesshomaru marvels at his brothers patience with the human. Sesshomaru has no need for humans and says Kagome must die for pulling out the sword. He attacks her with poison from his hand encasing her and the Tetsusaiga in goo. He then turns his attack on Inu Yasha.
As the brothers fight, Inu Yasha thinks of his mother and the “murdered” Kagome. His single minded desire to avenge them gave him strength enough to shatter Sesshomaru’s armor. Just when it starts to look like Inu Yasha might win the fight, Kagome breaks out of the poison goo. She was protected by the Tetsusaiga and the brothers are shocked to see her still alive. Kagome gives Inu Yasha the sword. Sesshomaru challenges Inu Yasha and transforms into his full demon form. The fight seems to have gone out of Inu Yasha as he doges Sesshomaru’s attacks. The dog demons slobber is also poison and it begins to dissolve the bones in the tomb. Kagome, Myoga, and Jaken climb out onto fathers shoulder. As Inu Yasha tries to escape the tomb, Sesshomaru comes up behind him and puts him in his mouth. He leaps out of the tomb as Inu Yasha struggles to free himself.
Inu Yasha breaks away from Sesshomaru. He’s furious and thinks the sword is worthless, comparing it to a walking stick. Kagome cheers him on and he tells her she’s about to die. Kagome starts to cry and Inu Yasha tweeks out a little. Inu Yasha tells her to shut up and let him protect her.
He walks out to meet Sesshomaru and the Tetsusaiga starts to pulsate in his hand. Inu Yasha attacks with the sword and cuts off Sesshomaru’s left arm. The sword had transformed into a fang. The fang of his father. He attacks Sesshomaru again and the demon dissipates and flees. Jaken goes running after him. Inu Yasha Kagome and Myoga check out the transformed Tetsusaiga. Later at Keade’s, Myoga says that Inu Yasha’s father had the sword forged to protect Inu Yasha’s mother and that it was Inu Yasha’s desire to protect the mortal Kagome that made Tetsusaiga transform.