One decade later, Towa is reunited with Setsuna, when she leaves the modern era through the vast time-traveling power of the spiritual Sacred Tree of Ages.

To restore them, the half-demon twins embark on an adventure, alongside their half-demon bounty hunter cousin Moroha, the fourteen-year-old daughter of Kagome and Inuyasha, who lacks full knowledge of her parents' fate; except that her human mother is an uppermost-level priestess and that her equally impulsive and overconfident father is half dog-demon and half-human, just like her half-first twin cousins.

At the same time, the unparalleled time-based unsurpassable entity is harboring adult Rin in suspended animation for her husband Sesshomaru due to her fatal connection to Zero, the elder sister of Kirinmaru and creator of the seven mystical Rainbow Pearls, whose respective mighty demonic abilities rival those of the Sacred Jewel of Four Souls itself.

Setsuna has her Kanemitsu no Tomoe upgraded by Tōtōsai into the mighty Yukari no Tachikiri, which can cut the invisible red threads of fate.

Towa receives the legendary cosmic sword Zanseiken from Kirinmaru's late daughter Rion, whose soul is contained within an artificial body created by her father.

After saving Sesshomaru, Towa discovers that Kirinmaru allowed her to keep Zanseiken so that her soul is eventually extinguished by using its power so that he can use her body as a living vessel for Rion against the wishes of his undead daughter while Moroha is given a spiritually-empowered longbow made by Inuyasha and Kagome, which greatly boosts the effectiveness and spiritual energies of her sacred arrows.

Using Akuru's time-based pinwheel, the Half-Demon Princesses travel back to the modern era to destroy the comet themselves, with Kirinmaru chasing after them.

However, he double-crosses the girls and brings the Grim Comet to the feudal era to grant Kirinmaru's wish in obliterating it from the plane of existence and show Rion various countries and states from around the modern world.

[3][4] The series was produced and animated by Sunrise, directed by Teruo Sato with main character designs by Inuyasha original creator Rumiko Takahashi.

[24] A manga adaptation by Takashi Shiina, with script cooperation by Katsuyuki Sumisawa,[25] started in Shogakukan's Shōnen Sunday S on September 25, 2021.

[47] In her review of the first two episodes, Kara Dennison of Otaku USA made positive comments about the series, praising its cast and its way to "echo the story of Inuyasha without simply retreading it.