Dejected and downcast, Kiyohime trailed behind Su Mo into the room. The soft thud of the door closing behind her snapped her out of her daze.
"Wait, Lord Su Mo!" she blurted out. "Even if we might be together in the future, nothing is set in stone yet. Isn't replenishing mana at this point… a little too fast?!" She panicked, waving her hands as if to ward off some invisible force. Kiyohime, of course, knew exactly what "mana replenishment" implied. There were many ways to do it—but only one method that was truly efficient. And now she'd been called into a room, alone with him. What else could it possibly mean?
While she was flattered by Su Mo's earlier compliments, her feelings hadn't progressed that far. Not to mention—this would mean betraying her Master.
That can't happen. I can't allow that.
But just as she was waving her hands in refusal, Su Mo tilted his head slightly, confused.
"…Did you misunderstand something?" he asked. "I only mentioned mana replenishment as an afterthought. The main reason I called you here was to help me test something." He raised the magic tome Illya had brought and waved it lightly.
—Saint Graph Manipulation Techniques.
"Huh?" Kiyohime blinked in surprise.
"So… when you invited Saber earlier, it was for this too?"
"Yes," Su Mo nodded. "Okita's inherent skill Weak Constitution is holding her back. I wanted to see if this technique could help remove that curse."
"But right now, I'm still not capable of pulling that off. Today I just want to run some basic tests on this Saint Graph manipulation."
"If Sakura needs Okita with her, then you—being a Servant too—can help me test it. Is that alright?" He gave her a questioning look.
Su Mo hadn't bothered asking for Kiyohime's consent earlier, since to him, this was a minor, harmless task. Plus, if the experiment worked, it would benefit her as well. There was no reason she would say no.
Upon hearing his explanation, Kiyohime finally let out a breath of relief.
Thank goodness… so it wasn't that kind of situation!
She did feel a tiny bit disappointed for some reason—but more importantly, she hadn't betrayed her Master. That was enough for her. Once she got back, she'd just explain everything clearly. Her Master would surely understand. With her spirits lifted, she looked up and smiled brightly at Su Mo.
"If it's just helping Lord Su Mo test the technique, then I don't mind at all!"
After all, it wouldn't take much time.
With that thought, Kiyohime obediently sat down in front of Su Mo, settling into a demure seiza posture. She looked heartbreakingly adorable like that, and even Su Mo couldn't help but glance twice at those white stockings before focusing back on the book. Then, without distraction, he immersed himself in the study of the spiritual foundation manipulation techniques Illya had brought.
At their core, Servants were merely downgraded versions of Heroic Spirits. The Heroic Spirits within the Throne were more akin to spirit-like existences—much like the gods from the Campione world.
Servants, therefore, were merely projections—fragments or incomplete incarnations of the true Heroic Spirits.
If a Heroic Spirit were water, then classes like Saber, Lancer, and Rider were vessels. The Servant was what you got by pouring that water into a container.
But the portion that didn't fit in the container—the excess—was simply discarded. This was why a Servant's strength could never match that of their full Heroic Spirit counterpart. The Saint Graph manipulation technique aimed to alter this very foundation—the Saint Graph of the Servant.
If one could widen the foundation—that is, expand the container—then the Servant's power would naturally increase. This process was known as Ascension.
It involved gradually summoning and reinforcing the saint Graph multiple times to enlarge it. However, Ascension had its limits. After all, the Heroic Spirit's original power was fixed. Even if you made the container bigger, the total amount of "water" stayed the same. There was only so much strength to pour.
That was one way—altering the Saint Graph quantitatively.
But the technique also offered a second route: qualitative alteration.
Imagine two vessels holding the same amount of water—one basic, the other forged from divine materials. Their effectiveness would be completely different. In other words, if you could replace an ordinary Saint Graph with a higher-tier one—say, a Grand-Class foundation—the Servant's power would increase dramatically.
However, to withstand a Grand-Class Saint Graph—
Even for a Servant, certain qualifications were still necessary. Not everyone could handle it.
Beyond adjustments to quality or quantity, there were many other ways to modify a Saint Graph—adding, deleting, altering... any form of manipulation one could imagine. Removing something like Okita Souji's [Weak Constitution] curse would be child's play.
However, all those advanced modifications required one fundamental prerequisite: mastering the Third Magic.
Only a practitioner of the Third Magic could freely manipulate a Servant's Saint Graph without restrictions. Even Illya, a product of the Heaven's Feel, struggled to reach that level. After all, materialization of the soul—the manipulation of soul-based phenomena—was the true domain of the Third Magic.
Though Su Mo couldn't perform the more intricate operations yet, basic experimentation was still possible. As he pored over the contents of the magical tome Illya had given him, time continued to pass quietly. Before long, midnight had arrived.
Kiyohime, who had thought the session would be over quickly, was caught off guard by how long it was dragging on. If she'd still had any confidence earlier about explaining things to Sakura, now she wasn't so sure. Spending several hours alone with Su Mo? Who in their right mind would believe nothing had happened? Just then, Su Mo finally removed his hand from her white-stockinged legs.
"That's about all I needed to verify. Thanks for your help."
He had now thoroughly reviewed and confirmed the contents of the tome. Once he obtained the Holy Grail, he could begin applying the technique in full. Removing Okita's curse? Easy. Upgrading her to Devil Saber Okita? That wouldn't even be a challenge.
"Finally done!"
Even as a Servant, Kiyohime's legs were starting to feel a bit numb. She began to stand, already thinking about how to explain herself to Sakura. But before she could move, a rustling noise came from the hallway.
Knock knock!
Someone was at the door.
Panic surged in Kiyohime's heart.
She hadn't been informed that Illya would be visiting. The first person who came to mind was Sakura—come to check if her so-called helper was still alone in Su Mo's room this late at night. It felt like being caught in the act—like a mistress who got discovered.
"If I get caught right now, there's no way I can explain this!"
And it was already midnight! Panicking before Su Mo could even react, Kiyohime completely forgot that she could still shift into spirit form. She desperately looked around for a place to hide. Unfortunately, Su Mo's room had only recently been cleaned up. There wasn't even space for a rat to hide, much less a person. After a quick scan, she made a bold decision—and dove straight under Su Mo's blanket, burying herself like an ostrich.
"What are you doing?" Su Mo asked, baffled.
"Please don't tell Sakura I stayed here this late!" Kiyohime's voice came muffled from under the covers, only her horns poking out. "She'll get mad!"
The sight was… oddly cute.
However—
"I don't know why you're being so secretive," Su Mo muttered, "but do you really think hiding like that is going to fool anyone?"
"You're a Servant—just turn into spirit form!"
"Oh—right!"
Only now did Kiyohime remember. She instantly shifted into spiritual form and vanished.
"…Haa."
Su Mo sighed. Honestly, even if she was in spirit form, Sakura—being her Master—would absolutely be able to sense her presence. But he chose not to say that out loud.
"Come in."
He called out toward the door. The door creaked open, and Illya cheerfully hopped inside. Seeing that it wasn't Sakura, Kiyohime let out a breath of relief. Still, since she was already invisible, reappearing now would just make things more awkward. She figured she might as well stay hidden. Then she watched as Illya glanced around the room once.
"Papa," the girl asked with a grin, "where's Mama Kiyohime hiding this time?"
"I can sense her presence. She was definitely here for another one of her nightly sneak attacks, wasn't she?" Kiyohime nearly fainted. How did she know I was here?! Su Mo was just as surprised.
"How did you know she came by?"
Illya giggled.
"Because Mama Kiyohime always used to sneak into your room at night! I remember whenever I woke up late and wanted to sleep with Papa, I'd often catch her sneaking around, trying not to get caught. It was really funny!" Her tone was innocent and playful. But Su Mo's expression turned oddly complicated.
Given Kiyohime's intense and passionate nature, that kind of behavior didn't seem far-fetched. Still, thinking back to her panicked refusal earlier, this current Kiyohime felt like a completely different person.
Meanwhile, Kiyohime—still hidden—was burning red with shame.
Future me did stuff like that?!
Sneaking into Lord Su Mo's room every night?!
Yikes. Knowing her own personality, it wasn't impossible… but if that was really the case, didn't it mean she had outright betrayed her Master?
That's not okay!
Kiyohime fell into complete disarray. Inside her heart, a new thought began to blossom. If this truly was a destined future, did it mean she and Su Mo were fated to be together? When seen in that light… it did feel a little romantic. But what about Sakura? How was she supposed to explain any of this? Now caught between burning emotions and moral restraint, the lovestruck maiden found herself at a loss.