Episode 176

Sesshomaru in the Underworld is the 9the episode of InuYasha: The Final Act.

Summary
Inuyasha and his group are still coming to terms with Kikyō's death. Kōga leaves the fight against Naraku to them.

Elsewhere, Sesshōmaru is aggravated by Meidō Zangetsuha being unable to become a full circle, which is it's perfected form. Seeking answers on how to make the technique evolve, Sesshōmaru visits his mother for answers. However, will he be willing to continue his quest to make Meidō Zangetsuha stronger? Even if it may cost the life of someone he cares for?

Plot
Rin asks Jaken why Sesshōmaru has taken them to a field in the middle of nowhere. Jaken doesn't know, but the fact Sesshōmaru has been looking for something for the last three days makes it important. Tenseiga pulses as they talk. Rin notices Kohaku staring off into the sky, thinking of Kikyō; he saw he soul ascend the previous night just like everyone else did. Rin offers his condolences to Kohaku, who only laments being weak. Sesshōmaru notices a dog demon flying the sky and transforms, flying along with it and crashing into the ground. Once the smoke clears, Sesshōmaru is back in human form along with the other dog demon, revealed to be female. She addresses Sesshōmaru without honorifics, making Jaken angry. She ignores him and continues, saying that Sesshōmaru must have questions about Tenseiga; what other reason would he have to seek out his mother? This shocks Jaken.

Elsewhere, Hakkaku and Ginta have arrived, learning Kōga lost his shards, something frustrating him. Kōga walks over to Inuyasha and kicks him, but gets a subdued response from him. Inuyasha wonders if Kōga's leaving; he is, he'd only slow them down now that he lacks his shards. Kōga yells that Inuyasha isn't the only one whose suffering. Inuyasha calmly accepts this and Kōga says he feels terrible for leaving Kagome behind; Inuyasha agrees again. Kōga smacks him on the head, freaked out by Inuyasha agreeing with him. Inuyasha snaps back to normal, saying he's being kind because Kōga's injured. Kōga tells Kagome that Inuyasha needs her by his side to help him recover. Inuyasha tells Kōga the loss of his shards wasn't in vain. Kōga hopes Inuyasha is right and tells Kagome to find him if she gets tired of Inuyasha. Kōga takes, surprisingly being faster than Ginta and Hakkaku. Inuyasha then notices a cloud shaped like a dog, which carries Sesshōmaru's scent.

Back to Sesshōmaru's group, they have arrived at a castle in the sky, where Sesshōmaru's mother lives. She is confused by Sesshōmaru keeping two human children with him; he used to despise them. She wonders if he intends to eat them. Sesshōmaru changes the subject, asking if the Inu no Taishō told her of a way to strengthen the Meidō Zangetusha. She explains that he only gave her a Meidō Stone, which was to be used if Sesshōmaru came seeking advice about Tenseiga; it would place Sesshōmaru in danger, but she is to not be worried or concerned about it. Jaken quickly sees Sesshōmaru must have inherited his mother's cold-heartedness. Sesshōmaru has his mother use the Meidō stone, summoning a Hell hound, which is unaffected by the Meidō Zangetsuha. The beast swallows Kohaku and Rin, returning to the Underworld. Sesshōmaru follows after them, but is warned by his mother it would be foolish to go after the humans. He lies, making seem like he's going to slay the hound. When the path closes, she says that noone can return alive, pretending to be distraught. Jaken is annoyed she chose NOW to say that.

Arriving at the path to the Underworld, Sesshōmaru follows after the Hell hound. In the world of the living, Jaken is crying about how cruel Sesshōmaru's mother is; he wonders what will happen to Sesshōmaru. She only says sacrifices are necessary to master swords. In the Underworld, Sesshōmaru sees pallbearers try going for Rin, but uses Tenseiga to slay the Hound and the minions of the Netherworld. Sesshōmaru's mother sees this from her Meidō stone, explaining what has happened to Jaken. This confuses Jaken, who is asked by Sesshōmaru's mother about Rin's relationship to Sesshōmaru. Jaken expresses his jealousy at how Rin is favored over him. She says Rin will die. In the Underworld, Kohaku awakens thanks to his jewel shard, but Rin remains unconscious. Skeletal birds begin attacking them, forcing them to run away. Sesshōmaru fights off the demons, but is force to rescue Kohaku when the path begins crumbling. He is left to wonder what lays atthe end of the path, Jaken asks Sesshōmaru's mother the same question, only to learn that Sesshōmaru will never be able to return, let alone Rin and Kohaku.

Kohaku informs Sesshōmaru that Rin stopped breathing, something that shocks him in place. Sesshōmaru's mother watches this and says the Underworld's darkness is in front of him. He orders Kohaku to place her down and attempts to revive her again with Tenseiga; however, he cannot see the pallbearers of the Underworld, something that fills him with great despair. Jaken listens as Sesshōmaru's mother explains that unless the pallbearers of the Underworld can be seen, Rin cannot be revived; if the guardian of the Underworld if slain, Rin may be given her life back. However, it resides in the Underworld, and no one can ever return from there; Rin is dead, with no way to return to life. In the Underworld, Sesshōmaru's rage begins to grow because Tenseiga will not bring back Rin again. Kohaku begs forgiveness, but Sesshōmaru now regrets bringing  Rin with him; he should have left her at a human village.

Just then, darkness rushes over them and takes off with Rin's body. Sesshōmaru and Kohaku give chases; they run into the darkness of the Underworld. In the World of the Living, both his mother and Jaken are shocked by this. Jaken begins crying, unable to live. Jaken is quieted when Sesshōmaru's mother explains that she will open a path back to the World of the Living for Sesshōmaru to return through; she is not a heartless monster. Back in the Underworld, Sesshōmaru is still giving chase to Rin just as the portal back to the World of the Living opens; his mother urges him to come back as Tenseiga has been strengthened. He orders Kohaku to take the path back to the World of the Living, but both take off. Sesshōmaru's mother decides to leave him to his fate.

Sesshōmaru soon comes to a heap of bodies. It begins sucking them into a black hole, Sesshōmaru pulls Kohaku back from the pull's reach as he almost got sucked in. He sees the Underworld Guardian holding Rin and is preparing to send her in next until Sesshōmaru slays the guardian. He orders her to wake, but finds that she isn't. Sesshōmaru's mother sees this in her stone, asking Jaken if Tenseiga brought Rin back before. Once he tells her yes, she explains Rin cannot be brought back. In the Underworld, Sesshōmaru grieves, dropping Tenseiga as he realizes that he can not save her. His rage boils beneath the surface, blaming himself; to him, nothing is worth losing Rin's life. Tenseiga begins glowing and the corpses begin moving towards the blade, seeking salvation. Sesshōmaru picks up his blade and grants the dead souls salvation, covering them in a blinding blue light. Sesshōmaru's mother sees this in the stone, becoming surprised.

Sesshōmaru is heard calling out "Meidō Zangetsuha," and a Meidō opens in the World of the Living (it's now in the shape of an eye). Sesshōmaru exits the Meidō with Rin's body and Kohaku. Sesshōmaru lays Rin down with Jaken looking at her corpse. Sesshōmaru's mother notices he's sad, but wonders why; Meidō Zangetsuha has become stronger, the reason he sought her out. Sesshōmaru's calm barely remains intact as he angrily asks his mother if she knew Rin would die. She informs him that she's learned Rin was already brought back by Tenseiga; however, the blade is limited to "one revival per person"; one can only bend the laws of life so much. The Inu no Taishō needed Sesshōmaru to learn sorrow and fear for someone's death; the sword of healing can only be held by one of with a caring heart.

Jaken begins crying, explaining that Sesshōmaru is not one to do so, so he is doing so on his behalf. This shocks his mother, who realizes Sesshōmaru valued the human girl's life over power. She tells Sesshōmaru that "this is her last chance" and places the Meidō stone around Rin. The stone glows  and Sesshōmaru's mother explains the light is Rin's life. Rin opens her eyes, shocking Sesshōmaru. He places his hand on Rin's face; Rin is happy that Sesshōmaru is there. Jaken thanks Sesshōmaru's mother in his place; she asks if Sesshōmaru is happy now. Jaken tells her Sesshōmaru is very happy. This confuses her. All Sesshōmaru's fuss over a human girl; she notes Sesshōmaru has inherited one of the Inu no Taishō's more unusual traits. Upon leaving, Sesshōmaru's mother inquires as to how Kohaku could survive in the Underworld, but Rin couldn't; he explains about the shard in his neck. She warns him that Tenseiga cannot bring him back.

Elsewhere, Kagome tells everyone Kikyō's final words; she wanted her to protect Kohaku and the light in his shard. They all decide to go and find him.