Type-Moon World — Ryūdō Temple.
A figure clad in a hooded robe stood before a massive magic circle, her slender, graceful silhouette outlined by the pulsing light beneath her feet. She slowly raised her hands and began to chant.
"Fill. Fill. Fill. Fill. Fill—!"
...
"I hereby declare. Hearken, o body, and obey my command—my fate and thy sword are bound as one…"
...
"I vow to accomplish all the good in this world. I vow to annihilate all the evil in this world…"
"Thou art the Seven Days bound by the Three Great Words, come forth from the Wheel of Restraint—Guardian of the Scales…"
As the woman's voice echoed endlessly through the night sky above Ryūdō Temple, the magic circle blazed brighter and brighter, its radiance piercing the darkness like a second sun.
When the chant finally came to an end, a crest composed of three Command Seals—shaped like a demonic sigil—slowly surfaced on the back of the woman's hand.
Gazing at the Command Seals now etched into her skin, and at the silhouette within the magic circle growing ever clearer, a smile curled beneath her hood.
"Sōichirō-sama, the Heroic Spirit summoning was a success. With this, our chances in this Holy Grail War have increased dramatically.
"I don't know why the rules of this Holy Grail War have changed, but with two Heroic Spirits on our side… there's no way we can lose this time."
Caster—Medea—knew she had gambled correctly.
By exploiting her Noble Phantasm Rule Breaker, combined with her Class as Caster, she had boldly slipped through a loophole in the Holy Grail War's rules.
If any magus could summon a Heroic Spirit, then why couldn't she—the greatest magus of the Age of Gods—attempt to summon one herself?
That was Medea's reasoning.
And by using her Noble Phantasm, which could shatter any contract or spell, along with her terrifying depth of magical knowledge, Medea truly became the first Heroic Spirit to successfully summon another Heroic Spirit—becoming a Master herself.
"Eh? That's not right.
"After completing the mission, I should've been sent back to the main world… but this doesn't look like the world I came from at all…"
Ren Kuroda had originally been in another world entirely. After completing the mission 'Ascend to Demon Lord Seed' and sending Spider Princess and the others back to their original world, the System should have returned him to his home world.
Yet now, stepping out of the enormous magic circle beneath his feet, Ren surveyed his surroundings—then glanced at the man and woman standing before him—and realized something was very, very wrong.
He had been transported to yet another world.
"O summoned Heroic Spirit," Medea said coolly, raising the hand marked with Command Seals to display her authority. "State your Class and your True Name. I am your Master."
Because this was an irregular, rule-breaking summoning, Medea—despite being the Master—was unable to see Ren's detailed Servant information.
Unfortunately for her, Ren's expression was one of pure bewilderment.
He still hadn't figured out why he'd suddenly been dragged into yet another world. The two people before him looked oddly familiar, yet he couldn't quite place them.
But the moment Medea spoke the words "Heroic Spirit," "Class," and "True Name"—
It clicked.
Holy crap… I got summoned into the Type-Moon world?!
Now that he realized where he was, the sense of familiarity snapped into focus.
The man and woman before him weren't just vaguely recognizable—they were unmistakable.
The homeroom teacher of the Fifth Holy Grail War, Kuzuki Sōichirō.
And his Servant—Caster Medea.
So that meant… as the one summoned by Caster, he had replaced that poor, shut-in swordsman—
Sasaki Kojirō?!
As Ren sank his consciousness inward, he discovered something new—an interface entirely separate from his usual System panel.
A Servant Status Screen.
Name: Ren Kuroda(A great yokai of unknown origin from a forgotten era)
Alignment: Chaotic · Neutral
Class: Assassin
Parameters:Strength: A+Endurance: AAgility: AMana: A++Luck: B
Noble Phantasm:Sunwheel Blade (B+ Rank)
Magic Resistance: APossesses extremely high resistance to magecraft. Can effortlessly nullify spells of three verses or lower. Even High Thaumaturgy and ritual-level spells struggle to cause harm.
Personal Skills:
Infinite Martial Mastery (A+++):Peerless combat skill from a bygone era. Mind, body, and technique are perfectly unified, allowing full combat performance regardless of mental interference.
Five Elements Sorcery (B Rank):Possesses foundational cursecraft knowledge. When combined with exceptional mana capacity, can easily unleash Five Elements spells rivaling magecraft of six verses or higher.
Presence Concealment (A Rank):A standard Assassin skill. Exceptional ability to erase one's presence—difficult to detect even with specialized detection methods.
Monstrous Strength (A+ Rank):As a half-human, half-yokai existence, possesses mythological-level brute strength. Automatically activates to temporarily raise Strength to EX Rank.
Oni Transformation: Rampage (EX Rank):By awakening yokai blood, all parameters increase by one rank. After use, the body enters a brief weakened state.
Even with his familiarity with the Type-Moon world, Ren couldn't help but fall silent as he stared at stats that could effortlessly obliterate over ninety percent of all Servants.
Truthfully, his abilities hadn't changed much from before—many had simply been renamed or consolidated.
Infinite Martial Mastery was clearly a fusion of his blade techniques like Wind, Forest, Fire, Mountain, along with his unarmed combat skills.
Five Elements Sorcery was his so-so onmyōjutsu.
Monstrous Strength hadn't even bothered to change its name.
Oni Transformation: Rampage was essentially his old Half-Oni Form, though it had clearly been nerfed by the Grail due to how absurd it was.
What was more, the newly acquired skills Demon God King and Yokai King's Contract were nowhere to be seen.
Ren could even feel it—this world imposed certain restrictions on him, preventing those abilities from activating at all.
Though he had no idea why he'd been summoned, one thing was clear.
He was now undeniably a participant in the Holy Grail War.
He tried to contact the System—
—but the bootleg piece of junk seemed to have crashed completely, offering no response whatsoever.
Watching Ren stand there in silence, Medea's patience finally snapped.
She was a magus of the Age of Gods—the one closest to true Magic.
Arrogant by nature.
How could she possibly tolerate being ignored?
Especially with Sōichirō standing right beside her—there was no way the infatuated Caster would allow herself to appear incompetent.
"Unknown Heroic Spirit," Medea declared sharply, "I am the Master who summoned you. You will obey my commands and help me obtain the Holy Grail!"
Ren slowly turned his gaze toward her, utterly unimpressed.
"I know you're the one who summoned me," he replied lazily. "But why should I listen to you?
"If it weren't for you, I'd be sprawled on my couch right now, binge-watching the latest anime.
"And if I'm not mistaken… you're the infamous 'Witch of Betrayal,' aren't you? Hearing you talk about obeying one's Master—now that's a real novelty."
The instant those words left his mouth, Medea's mana exploded outward, visible to the naked eye as her fury shot straight through the roof.
Witch of Betrayal.
One of Medea's absolute taboos.
Just as she was about to teach this insolent Servant a lesson, a calm hand rested on her shoulder.
Kuzuki Sōichirō spoke evenly.
"If I recall correctly, when you explained the Holy Grail War to me, you said that each Heroic Spirit's True Name is a closely guarded secret.
"And when you summoned him, you only identified yourself as his Master.
"So tell me—why is it that you, the Master, don't know his identity… yet he knows yours?"
Medea froze.
The fury drained from her expression.
That was right.
The Command Seals were clearly on her hand—she was the Master, and he was the Servant.
So why couldn't she see any of his information?
And why had her own True Name been exposed instead?
"I command thee by my Command Seal—" Medea intoned, raising her hand, "—reveal thy true origin!"
Each Master possessed three Command Seals—precious, versatile tools capable of forcing obedience or empowering a Servant.
Once all three were spent, a Servant would all but escape the Master's control entirely.
That was why Masters rarely used them lightly—especially with rebellious Servants.
But Ren Kuroda was far too unsettling.
The fact that he could pierce her identity left Medea no choice but to act.
One of the Command Seals on the back of her hand began to fade, transforming into raw magical energy as it surged toward Ren.
Yet to Medea's shock—
The Command Seal, which should have exerted absolute authority over any Servant…
…failed to produce the effect she expected.