When Souta arrived at the Tohsaka residence, he saw Illya perched on a chair far too big for her petite frame, chatting with Rin about something serious. Her small legs swung back and forth adorably.
As soon as they noticed him, both girls stood and walked over to greet him.
"Big brother, welcome."
Illya curtsied politely, maintaining her usual calm, emotionless expression—clearly not the type to show feelings easily.
"Sorry to trouble you again."
Rin was much warmer in her greeting. She led Souta to a seat on the right and even served him tea.
It looked like a guest room—spacious enough, but for some reason, it gave off a slightly dusty, neglected vibe.
Noticing Souta's glance around the room, Rin coughed awkwardly and commented, "We don't really use this room much, so just bear with it."
"No worries, I'm not that picky."
Souta waved it off, took a sip of tea, and got straight to the point:
"Alright, let's hear your plan."
"Huh? What plan?" Rin looked confused.
"The plan to change the past." Souta gave her a suspicious look.
"Don't tell me you've got nothing prepared?"
"Well... you came over so fast, Illya and I didn't have time to finalize anything." Rin looked sheepish.
Souta rubbed his forehead. "Alright, let's all sit down and figure it out together."
They pulled their chairs close to talk more easily.
Suddenly, Illya chimed in:
"Big brother, last time you peeked at me while I was bathing, didn't you?"
"...Pff—!" Souta nearly choked on his tea.
They were discussing plans, why bring that up now?!
And worst of all, he couldn't even deny it.
Last time, Illya had asked for some cup noodles, and he created a few and teleported over to her castle to deliver them—only to find her naked in the bath at that exact moment. He had caught a glimpse of her delicate, undeveloped body...
"You... seriously did that?!" Rin eyed him warily.
"It was a misunderstanding! Just bad timing! I only dropped off the food and left immediately—no peeking involved. Besides..."
"What's even worth seeing on a nine-year-old? I treated her like a kid, that's all."
Illya huffed, clearly annoyed.
Rin nodded in agreement. "Yeah, nothing worth seeing."
"Rin, I'll kill you!"
Illya glared daggers at her, ready to summon Heracles on the spot.
Sensing the surge of magical energy, Rin twitched and quickly said, "Alright! Let's stay on topic, shall we? Souta, stop sidetracking!"
"..." Souta's face was expressionless.
Was she seriously pinning this on him just because he's easygoing?
He gave Rin a side-eye, then got serious:
"So, your goal is to save your families, right?"
"Exactly. I want my parents to survive safely, and I want to save Sakura too. And..."
Rin sighed and added, "Uncle Kariya."
"Matou Kariya...?" Souta was surprised. "You want to save him?"
In the Fourth Holy Grail War, Rin's mother, Aoi Tohsaka, had been manipulated by Kotomine Kirei into thinking that Kariya had killed Tokiomi. When she confronted him, Kariya lost control and strangled her into unconsciousness. Although Aoi survived, the oxygen deprivation caused severe brain damage. She became paralyzed and mentally impaired, dying before the Fifth War.
"Uncle Kariya was just a pawn... a pitiful man who was manipulated."
Rin shook her head. "I don't hate him. He only wanted to save Sakura but lacked the power. The true culprit is Kotomine Kirei."
"So, four people on your end: your parents, Sakura, and Kariya."
The system mission was to help them rebuild a happy family—so saving them, not fighting, was the real objective.
Though realistically, some fighting was inevitable.
Souta turned to Illya:
"Illya, who do you want to save?"
"My mother." Illya answered instantly.
"What about Kiritsugu?"
"Whatever." Illya turned away with a pout.
Clearly, she hadn't forgiven her father.
Souta scratched his head, unsure how to handle it.
He had mixed feelings about Kiritsugu himself—a terminal case of chuunibyou.
"Souta, the system asked you to help us rebuild our families, right? Maybe you should save Kiritsugu anyway, just in case the system flags it as a failure."
Rin made the pragmatic suggestion, then voiced another concern:
"By the way, if we mess with the past this much... won't it cause major problems? Like completely changing the future?"
He'd often wondered if changing the past to save people was really saving them.
Did Shido killing Origami's tragic past count as killing the original her?
Saving someone from death was one thing—but changing their suffering could be like erasing the person they were.
The altered version might share the same soul, but the memories would be different.
It felt like a philosophical rabbit hole.
Souta sighed and shared his thoughts.
Rin and Illya both fell silent.
"I once asked the system: when a new timeline replaces the old, as long as we—friend group members—aren't erased from existence, our memories will merge with the new timeline's. We won't forget a thing, and we'll still have our phones. It's a perk from the system.
But..." Souta shook his head.
"Everyone else's memories reset."