The Theories (a masterpost)
Kagura is likely the mom.
-work in progress-
Visual Evidence:
Towa had the exact same Naraku infant blanket when first introduced
Towa has red eyes like Kagura.
Setsuna and Towa have Kagura’s eye shape.
Towa and Kagura have very similar facial expressions.
Setsuna’s Naraku influences: very different color scheme from Sesshomaru, she appears for the first time to Kaede wearing her fur like Naraku’s baboon, Setsuna has the same hairline as Byakuya.
There is no way their other half is merely human, because there are other demonic genes visually in play.
Towa as a child had her hair up in a bun shaped just like Kagura’s, and Setsuna has a similar shape and color to Kagura’s hair.
The red in their hair is reminiscent of Kagura’s fan.
The childrens’ color scheme matches their parents’
Towa on her human night, much resembles human Naraku.
Powers Evidence:
Setsuna has wind powers. Kagura was a wind sorceress.
Towa's sword absorbs demonic energy, much like Byakuya's sword.
Setsuna’s Moon of the Resting Moth. Byakuya, Naraku’s incarnation and Kagura’s replacement, had moth powers.
Setsuna in episode 5, episode 8, uses tornado/whirlwind attacks. Her cyclone burst is pure wind.
Towa’s sword works more like Tokijin, rather than Bakusaiga, which was purely Sesshomaru’s. Tokijin was from Goshinki another Naraku demon. (Bonus: Kagura was the one who “gave” Sesshomaru Tokijin)
In episode 11 it was revealed that Setsuna has a resistance to venom which easily mirrors her father’s venom claws, while Towa has a resistance to poison mist, perhaps reminiscent of Naraku’s miasma. Kagura came from Naraku.
Less firm, but relevant evidence:
Towa holding her sword like Kagura
Setsuna in the field of flowers where Kagura died.
Kagura’s flowers mixed in with Setsuna’s dreams
Fans (3) in Setsuna’s ED background
Towa having a soft spot for male beauty, just like they portrayed Kagura in the series (praising Sesshomaru, blatantly saying Inuyasha and Koga are not her type of man)
Kagura’s theme song and Setsuna’s theme song are very similar, both melodically and rhythmically.
Setsuna’s scrunchie placement in Towa’s dream looking like Kagura’s feather
Sesshomaru reaching for Kagura’s feather with a pink light surrounding it, speculated to be her soul (bonus magazine translations!)
Paralleling the parents’ personalities, as well as Towa breaking her sword to save Setsuna (like Sesshomaru had broken Tokijin before finding Kagura) -Towa is rebellious like Kagura.
A phrase used at the beginning of the publicity for the sequel: "A wind of change is coming Sengoku."
Setsuna’s naginata is reminiscent of Hakudoushi’s naginata.
Consistent references to swallows (1, 2, 3)
The end of episode 10 was ominously focused on the wind. As well as the wind only blowing on Towa multiple times in episode 2.
Rumiko Takahashi’s interviews from 2019 further support Kagura being a likely candidate for being the mother of the twins and Sesshomaru’s wife. The feelings between them are highlighted, even going to say his emotions reached a climax with Kagura. In addition, RT has said that Sesshomaru has matured largely due to the influence of his wife. This was just last year, and Yashahime has been in the works for the past 3 years.
This year, the voice actors for Yashahime dropped that Kagura has a human heart.
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Extra: Why Rin is the daughter:
Kikyo’s “Daughter of Sesshomaru” is spoken towards Rin.
Rin’s age in the timeline making no sense to be the mom -she would have given birth at 13-14.
They still promote Rin as a child.
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Thank you everyone feel free to add whatever I missed and I will edit it in
A very special thanks to @divine-entertainment , @doombull , @teaandcrumpets !!!
