This was designed for hyper maximum feels saturation. Canon might be dubious.
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Chiyome never understand why Pink Caster with the... Weird... Magic Wand thingies was... well, very touchy-feely with her. No, not that kind of touchy feely. It seems she tend to get closer and talk to her, and always happy to do so even when Chiyome can only gave her short, vague reply.
So, one day, she asked her.
"Oh, it is bothering you? I am sorry-"
"No, not that. Is just that, well, I am aware I am not really the most social person there. I am not Nursery Rhyme-san, who knows many children stories, or Gilgamesh-kun, who had many stories and treasures to share. Or even Mordred-kun, who... loves to boast. So... it is just... unusual."
"...."
"Not that is bad, mind you. Just unusual."
"...Well, it's because you remind me of Miyu-chan."
"...Miyu-chan?"
"Well, yes, it was started when I'm still this normal grade-schooler and Ruby just kidnap me and-"
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"-It was a close call, but we managed it! We save the world, and nobody suffering for it. ... Well, not suffering much."
"Ah, I see. I reminded you of... this Miyu-chan?"
"Yes, you are so just like her! Even the serious side. I mean, you are more serious than her, but, well...."
"Ah, I see. ...Who is her true name?"
"Well, now we know her as Miyu Emiya, but Other Nii-san told us her name before, something like, uh, Sa... ki..."
"Sakatsuki"
"-Yes, that! Miyu Sakatsuki-"
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Her beloved had gone, claimed by war.
Her master, her retainer gone, killed by treacherous action, brought upon by war.
War. War. War.
They said it was necessity. They said it was inevitable. They said it was the greatest chance for everyone to prove themselves.
All she could see was wasteful, unnecessary destruction, anger, pain, and death.
Her final order had been given.
With The Ruin of Takeda, she would bring entire Japan to pay for her loss. They shall know her pain. Her anger. Her sadness.
Channeled through the Curse of Yamata no Orochi.
"Mother, are you okay? We are ready."
"...Yes. Let's do our duty."
All she needs to do is just sacrifice herself, and bring her daughter with her. Along with other 6 maiden.
...Can she does this?
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"-yome-san? Chiyome-san? Are you okay?"
Chiyome Mochizuki, awakened from her reverie, jolted.
"Uh, um, yes. I am... good."
"...You cried. Are you sure you okay?"
"...I am sorry, just... old memories. I am good now."
"...If you said so. So, yeah, she was Miyu Sakatsuki before then-"
"They said Sakatsuki line had power to grant a single wish."
Kuro chimed in.
"And Other-Nii-san said that for generations, unbroken-"
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Instead of expected pain, her daughter fall into the peace of sleep, along with other three younger girl.
"Uh, Master?"
Chiyome, silent, simply gave the other, each older girl a packet.
It contain documents and some money.
"Leave. Leave this war, and never look back. Take your sister with you."
"...But, but Master, the order-"
"I rescind that order. Nothing for us there. Nothing for me and my daughter there."
"...."
"...Please, this is my last wish. A wish of a mother. Please grant it, my daughters."
"...Y-yes, ma'am!"
"...Master, what about you?"
"I-"
Chiyome considered for a moment.
"Sakatsuki-san, would you take care for my daughter for me?"
"I-I- Yes, Mochizuki-sama!"
"...Thank you. Now, let me gave you all my last blessing-"
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"-That they only wished for their children-"
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"Please you all, grow up splendidly and healthy. Please live a fulfilling life-"
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"-To grew up healthy. Nothing more, nothing less."
"...That... That is... true?"
"..Uh, um, yes? I mean-"
Chiyome Mochizuki, once Priestess of Orochi, can't help herself anymore. She can only cried, and hug Illya and Kuro.
"Chiyome-chan?!"
"...Thank you.... thank you...."
"Ooooh, a big hug! Ritsuka wants a hug too!"
"Can we join, too?"
"Me too! Me too!"
And everybody was hugging together that day.
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