The next morning—
When Sakura woke up and found herself alone, she quickly heard the familiar sounds coming from the courtyard. She immediately realized Su Mo and Okita must be training again, practicing their swordsmanship, as usual.
Wearing the bunny-print pajamas Su Mo had bought her, the sleepy little girl yawned and padded toward the washroom to freshen up. While washing her face, she finally noticed the strange mark on her left wrist.
The red sigil was clearly unnatural. Being a well-behaved child, she had no intention of hiding it. Su Mo had taught her that keeping secrets like this would only make things worse. So, she put down her toothbrush and ran outside in her slippers, heading toward the courtyard. She showed Su Mo the strange pattern on her wrist.
"This is…" Seeing the mark on Sakura's wrist, Okita blinked in shock.
"A Command Seal…? The final Master is actually Sakura?!" Su Mo, too, was stunned. He held out his own left hand and placed it beside Sakura's. Both bore different patterns but the same kind of glowing red sigil.
Command Seals—symbols used to control and issue orders to Servants. The fact that Sakura had one meant she had been officially recognized by the Grail and chosen as the seventh Master.
"Does this mean… I'm like you now, Onii-chan?" The wide-eyed Sakura looked delighted. She didn't really grasp the meaning behind the Holy Grail War. She was simply happy that she now seemed to share something in common with Su Mo—something that made her feel even closer to him.
"Hmm…" Okita's expression turned a little strange.
"Well… technically speaking, Sakura's identity now means she might become Master's enemy." She said it half-jokingly, just trying to tease the little girl. After all, by the rules of the Holy Grail War, Masters were technically supposed to be competitors.
But—
"Eh?!" Sakura gasped.
"Then I don't want to be a Master! I don't want to be Su Mo-oniichan's enemy!" Her big teary eyes looked like they might overflow at any moment, and her little head shook frantically like a rattle drum. All she ever wanted was to help Su Mo. What if she became his opponent instead?! That would be a disaster!
Okita hadn't expected her joke to backfire so badly and quickly scrambled to comfort her.
"W-Wait! I was only joking, Sakura! Just a joke!"
"Actually, you don't have to be an enemy. You can become our ally instead! So please don't cry!"
"Really! I promise! Please believe me!"
"Uuuuh… Master, help me!"
Okita Souji, who clearly wasn't good at comforting children, flailed helplessly as she tried to soothe Sakura. Realizing her efforts were failing, she turned teary-eyed to Su Mo, clearly pleading for her Master to rescue her from this mess.
"..."
Watching the swordswoman—now nearly crying herself—Su Mo felt a wave of speechless resignation. It was one thing to tease a child and get caught in the backlash… but to end up crying in the process?
Okita, are you sure you're not just a comedy character?
"Don't worry," Su Mo finally said, patting Sakura gently on the head. "Just being a Master doesn't automatically make you an enemy. There's something called an alliance, you know."
After all, the Holy Grail War only needed Servants as sacrifices. The Masters were little more than disposable vessels in the bigger picture.
"And having you as a Master, Sakura, is actually a good thing for me."
He smiled as he said it—not as a way to comfort her, but as a genuine fact. Sakura was someone on their side. If she summoned a Servant, even one who wasn't strong in battle, that would still provide them with valuable information and insight. It would help Su Mo grasp the full scope of the battlefield. Besides, shifting from a 1v6 to a 2v5 scenario was always welcome.
Hearing this, the anxious little girl finally broke into a joyful smile.
"Really?! I can really help you, Onii-chan?!"
"Yeah." Su Mo nodded with certainty.
Now that she had his affirmation, Sakura bounced in place, visibly excited. The wish she'd entrusted to the Holy Grail had already come true—just being able to help Su Mo was everything she'd ever wanted.
"The only issue," Su Mo added thoughtfully, "is that with Sakura's current magical capacity, she might not be able to sustain a Servant."
He frowned slightly. While most of a Servant's magical energy was provided by the Grail itself, some parts—like maintaining physical form and combat functions—still required magical energy from the Master. And even that might be too much for someone like Sakura to handle at her age.
Right now, even Waver Velvet—still just a student—had significantly more magical power than Sakura.
"Then what do we do?"
Okita, now relieved to see Sakura back to normal, grew concerned again at Su Mo's words.
If the Master couldn't supply enough magical energy, then the Servant would either have to gain mana by killing people… or through more direct forms of magical replenishment from the Master. Neither was a good outcome, especially not with someone like Sakura.
Seeing the worried look in her eyes, Su Mo chuckled lightly.
"Relax. It's not a big deal."
"I never planned on having Sakura's Servant participate in combat anyway. If magical energy becomes a problem, I'll just handle the replenishment myself."
While there wasn't any long-term solution he could implement—he wasn't anywhere near capable of replicating the separation of magical energy supply line from the Command Spell line technique used by Lord El-Melloi Archibald (Kayneth)—there was still a workaround.
Kayneth may have been a disaster in the Grail War, but his magical expertise was unparalleled among the participants. Even Tohsaka Tokiomi paled in comparison. For someone like Su Mo, who was still getting familiar with the intricacies of Type-Moon's magic systems, it would take time before he could replicate such advanced techniques.
Still, with his own nearly limitless magical reserves, none of that mattered. He could simply act as a backup battery for Sakura whenever needed.
"Ehh?!"
Hearing this, Okita's eyes widened as her face instantly turned bright red.
She looked at Su Mo in disbelief, then stammered, "R-Replenish... as in, mana replenishment?!"
"W-Wait a second!"
"Master, Sakura is still just a child! Doing that kind of thing to her is...!"
She was clearly panicking now. Sakura was only six years old! Was her Master planning to commit an actual crime?! If it really came to that… well, she could probably handle some of the burden instead—
Just as she was about to blurt out something utterly dangerous, Su Mo sighed deeply and interrupted her.
"Where exactly do you think this is going?"
"Mana replenishment doesn't have to involve that kind of thing, you know!"
"Relax. I'm talking about standard, non-contact methods."
He wasn't so far gone as to consider doing anything to a child like Sakura.
And besides, magical replenishment didn't always mean doing something that would trigger a censorship warning. A simple divine blessing or protective enchantment could often serve the same purpose.
Hearing his explanation, Okita finally relaxed with a long sigh of relief.
Sakura looked curiously at the two of them, not understanding what they were talking about—but she couldn't shake the feeling that she'd just missed some kind of opportunity.
"Tomorrow marks the official start of the Holy Grail War," Su Mo said at last. He turned toward the little girl with resolve. "That means it's best if we summon your Servant today."
"Okay!" Sakura nodded obediently.
Since it was something, Su Mo wanted her to do, she had no objections at all.
"Let's get started then. It's important to identify the class of your Servant so we can plan ahead."
Summoning a Heroic Spirit didn't require much mana, which was why even someone like Ryunosuke—who wasn't a mage—could do it. While Sakura was still young, she had received some basic magical training. The summoning process itself wasn't a concern.
The real issue would be sustaining the Servant afterward.
But since Su Mo had volunteered to handle that part, there was no need to worry.
The three of them moved to the basement together.
Once the summoning circle was prepared, Sakura, under Su Mo's guidance, began the ritual to summon her Servant.
"Let silver and steel be the essence…"
"Let the foundation be stone and the archduke of contracts…"
The child's soft voice echoed in the dimly lit chamber.
Because they hadn't prepared a catalyst, Su Mo decided to let the Grail choose based on affinity. After all, he didn't plan on using Sakura's Servant for combat.
So even if the summoned spirit wasn't powerful, that was perfectly fine. In fact, a weaker Servant that required less mana would be far more suitable for someone like Sakura.
For Su Mo, the Servant's strength didn't matter nearly as much as Sakura's safety.
He just wondered—
What kind of Heroic Spirit would have strong affinity with someone like Sakura?
Sakura, for her part, had no idea what Su Mo was really thinking. Her eyes were filled with resolve.
After all, this was a rare chance for her to truly help Su Mo. Naturally, she didn't want to miss it. So, it didn't matter who the summoned spirit would be—as long as they could be of use to her beloved Onii-chan.
With that thought in her heart, she recited the incantation to the end.
"From the Seventh Heaven, attended to by three greet words of power…"
"Come forth from the ring of restraints…"
"Protector of the Holy Balance!"
As her childlike voice completed the chant, the summoning circle shone with brilliant light. A second later, the summoning succeeded. And atop the glowing circle, the figure of a Servant appeared.