The feudal era is saved from the Degenerate Age. Inuyasha helps repay Moroha's remaining debt. Towa and Setsuna receive kimonos from their mother, Rin. Towa, Setsuna, and Moroha accept a demon-slaying request from a mysterious man.

Setsuna directs Towa and Moroha as they continue to sever Rion's threads of fate. Each time a thread is severed, more of Rion's true feelings are revealed. As Kirinmaru fights Sesshomaru, he realizes the real reason he lost Rion.

Towa, Setsuna, and Moroha must save Rion, who has linked her fate with the Grim Butterfly, but Osamu Kirin stands in their way. Kirin declares that he and Rion should reign over the world in order to bring about true peace.

Osamu Kirin brings the Grim Comet to the feudal era. He convinces Rion that they are both hoping for the same world and promises to make it a reality. Meanwhile, Towa, Setsuna, and Moroha are stuck in the present day.

Inuyasha and the others have their hands full with the evil spirits pouring out of the burning Windmill of Time. The three girls and Osamu Kirin try to stop the Grim Comet from falling to the earth.

Osamu Kirin has been quietly exterminating the demons that have been appearing in the present day. He asks Towa, Setsuna, and Moroha to slay demons at the concert that is happening.

To destroy the Grim Comet, Towa, Moroha, and Setsuna must travel to the present day using the Windmill of Time, but Meidomaru stands in their way. Kirinmaru takes Rion and tries to travel across time by force.

In the present day, Osamu Kirin sees the Grim Comet approaching. Meanwhile, in the feudal era, Towa's life is in danger after she uses her Zanseiken. The Spirit of the Tree of Ages orders the half-demon princesses to go destroy the Grim Comet.

Wanting to prove his strength, Kirinmaru faces off against Sesshomaru. Towa summons the Tenseiga. Shippo waits for Inuyasha and the others at Gozu and Mezu's gate.

Inside the Black Pearl, Moroha is finally reunited with her parents, Inuyasha and Kagome. Inuyasha begins to see a way out of the Black Pearl. Meanwhile, Kirinmaru's attack leaves Sesshomaru gravely injured.

Kirinmaru takes the Black Pearl from Moroha and demands that she bring Akuru to him. Towa and Setsuna try to lend a hand, but Sesshomaru arrives at the scene to take on Kirinmaru instead. Meanwhile, Rion and Riku head to Mount Musubi.

Towa is consumed by rage and loneliness. Setsuna tries to stop her from killing Zero because the curse on their mother cannot be lifted unless Zero lets go of her regrets. Sesshomaru gives Moroha the Black Pearl.

Zero unearths Towa's sadness about growing up in the modern world and corners her with her memories of loneliness and suffering. Sesshomaru appears before the demon slayers and commands Setsuna to pay the Tree of Ages a visit.

Moroha and Takechiyo strike back against Shogen Mamiana. Setsuna experiences her first New Moon. Towa is trapped by Nanahoshi's eternity bugs.

Moroha learns about her parents' battle against Shogen Mamiana, the sealing of the Full Moon Raccoon Dog, and Takechiyo's exile from his clan. Setsuna is attacked by the snow demon Yukinyudo. Zero targets Towa on the new moon.

Riku is able to open his eyes again. He Towa's lavender hand cream in an attempt to store his vision. Does scent really impact his vision, or does he Only Have Eyes For Towa? Hachiemon and Takechiyo rescue Moroha. Setsuna frees Mahiruma and The Blessing Of The Five Grains from Gokoku.

Zero sets a trap in the garden of Nanahoshi, a demon who feeds on sadness. Kirinmaru pays Towa, Riku, and Rion a visit. Kohaku, Hisui, and Setsuna assist the chief of the demon slayers in the north.

Revealing that he was once the young lord of the Mamidaira Clan, Takechiyo hires Moroha as a bodyguard to help him with the familial strife at his home. During training, Kohaku teaches Towa an important lesson about learning to run away.

Setsuna is kidnapped by Princess Aiya, daughter of the deputy shogun. Wanting to escape her studies, Princess Aiya begs Setsuna to be her body double for a day, but the princess's new tutor turns out to be Hisui posing as his older sister Kin'u!

Rion used to travel the world with her father Kirinmaru, but one day, her soul was sealed deep within Mount Musubi. Longing for freedom and peace, Rion asks Setsuna to sever the thread of fate that connects her to her father.

To get their hands on the famous spiritual root, the three Yasha princesses must enter a territory surrounded by a powerful barrier. This will be an opportunity for them to ask themselves certain questions, but above all to obtain valuable answers.

Jaken recalls that fateful day fourteen years ago, when Zero placed a curse on Rin that would make her slowly rot away to an excruciating death. The three girls search for Bokusen-Oh, who may have a lead on the whereabouts of Towa's new weapon.

Remembering what Tōtōsai said about Towa being vulnerable, Setsuna goes with Moroha to find the Elements needed to Forge a new Sword. The lady that they seek takes notice of Setsuna's beauty and plots revenge. Towa and Riku join the side of Setsuna and Moroha while Setsuna detects the final thoughts of a man that accidentally killed each other from a misunderstanding. The ghost Ghost Devil hears the man's final thoughts and finally ascends. Riku prepares himself to search for the Elements that they need.

Jaken, Kirara, Mō-Mō, Moroha, Sesshōmaru, Setsuna, Tōtōsai, and Towa are in the war zone. During Towa's first attempt to use Tensaiga, she encounters The Dream Butterfly, which communicates Rin and The Tree Of Ages, and flies towards them. Not long after they are surrounded by Devils From The Underworld. Greatly Outnumbered, Moroha and Tōtōsai forge a Sword for Setsuna and takes the burnt out Tensaiga in for repairs.