[LONG Theory Thread] Zero: Hell hath no fury like a woman scorned. PROVERB, a woman who has been rejected by a man, can be ferociously angry and vindictive. (+) #Yashahime #InuYasha #InunoTaishō #Takemaru #Izayoi #sessrin
I am highly convinced (until TBA) that Zero and Inu no Taishō were lovers (she was his mistress) while still married to Sesshomaru's mother. It is widespread in many cultures for a king to have a royal mistress of high birth. (+)
Inu no Taishō and Sesshomaru's mom (InuKimi) had an arranged marriage. One of respect and admiration and some degree cared for one another. This is due to how she talks to Sesshomaru about his father in TFA Ep9. (+)
She also states that Sesshomaru lacks any charm in the Inuyasha manga Chapters 466-471. She also notes in both the odd feelings towards humans that her son has inherited from his father. Her reactions are slightly different in the manga and anime. (+)
I believe she was saddened at his death, but not to the level of Zero and Izayoi. Who created the black and rainbow pearls from their great sadness. I think his death also changed Izayoi's personality, making her incredibly depressed (+)
Zero felt humiliated and angry at him for taking a human as his bride and wife (but still loved him). This isn't just a scorn woman by unrequited love. This is the scorn of a lover that was tossed to the side, and her lover ends up loving and marries another. (+)
Zero seems to mock Sesshomaru for taking a human wife and having half-demon children. When he once hated them. She threatens his family, due to being humiliated by his father.
Zero also holds a significant amount of disdain towards Sesshomaru for taking a human wife and having half-demon children, as his father had done. (+)
Zero compares Sesshomaru to falling to ruin like his father. It makes me wonder, was she behind the events of Ryūkotsusei and Takemaru (3rd Inuyasha movie, EP53, and Ch188)?? (+)
Inu no Taishō dwelt with the daiyōkai Ryūkotsusei who was terrorizing the plains of Musashi, wounded in battle. He is then forced to run to a pregnant Izayoi's side when she (unknowing to her) is being kept captive by Takemaru. (+)
Zero had planned for her ex-lover's wife and unborn child to die at the hands of the jealous Takemaru. By giving the man knowledge of the lunar eclipse. InuYasha and Sesshomaru's twins are both born on the night of a lunar eclipse. IY3rdMovie and HnYEp15 (+)
Sesshomaru knew of Takemaru. No doubt, Zero did as well. Sesshomaru and Inuyasha's conversation in IY3rdMovie of Takemaru ( and no shit, Sesshomaru he wouldn't know of him...)
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Zero intended to use Takemaru's rage and feelings towards Izayoi with her being with a demon. To end their lives; however... (+)
Things obviously didn't go as planned... Zero consumed by her obsession, anger, and hatred ending up causing Inu no Taishō's death indirectly. Sesshomaru blamed Inuyasha and Izayoi for the death of his father when it was really Zero who caused his death. (+)
Okay, that's it, until we know more after ep 21 of Yashahime... anyone like my crackpot theory? 

