While Kaito was away on a trip with Fate, a lone figure arrived at the castle of the Death King, Isis Remnant, located in the northernmost reaches of the Demon Realm—the Land of Death.
The visitor was an insectoid demon with a total of six swords sheathed at her waist, three on each side. The magic power she radiated was immense, a clear testament to her extraordinary prowess.
This insectoid swordsman was Sirius. As a warrior possessing the strength of a top-tier Count-class demon, she reached out and touched the visitor's magic tool installed at the gate, her expression set in a mask of slight tension.
Before long, the massive gate swung open, and Polaris—a witch wearing a white pointed hat—stepped forward.
"Hmm? I wasn't told to expect any guests... Though I doubt anyone could wander this deep into the heart of the Land of Death just by losing their way."
"Forgive the unannounced visit. My name is Sirius... I have come to request a duel with one of the Six Kings, the Death King, Isis Remnant-sama. I realize this is a selfish petition, but I ask that you relay my request to her."
"...A challenge for Isis-sama?"
Hearing Sirius's intent, Polaris’s gaze sharpened.
"Just to be sure, you aren't an acquaintance of hers, are you?"
"No, we have never met."
"And you don't have a prior appointment for a spar?"
"I do not."
"...I see."
In an instant, Polaris’s magic flared with a piercing edge, and Sirius’s own power surged to meet it. Their auras collided in the space between them, the sheer pressure causing the ground to crack and splinter.
"The title of the Six Kings is not so light that we can simply allow any stranger who wanders by to issue a challenge... Wouldn't you agree?"
"I had heard she had gained subordinates, but I clearly underestimated just how powerful they were... Still, I have no objections to proving myself."
Polaris tightened her fists as Sirius moved her hand to the hilt of her sword.
"I am Polaris, a member of Isis-sama's household. If you truly wish to challenge her, you'll have to go through me first!"
"Allow me to name myself once more. I am Sirius... and I shall be passing through!"
Both were top-tier Count-class demons; facing one another in a state of battle readiness, they could easily grasp the depths of each other's strength. Just as they both braced for a violent collision, a quiet voice echoed through the air.
"...Wait... Polaris."
"Isis-sama?"
At the sight of the Death King, both Polaris and Sirius broke their stances almost simultaneously.
"...I... heard you..."
As Isis approached, Sirius sheathed her blade and dropped to one knee.
"It is an honor to meet you, Death King-sama. I am Sirius. I know this is insolent, but I have come to test my limits. Would you grant me a duel?"
"...Yes... I understand... Very well."
"You have my deepest gratitude."
"If that is your wish, Isis-sama... I shall prepare the barrier," Polaris added.
"...Please."
With Isis accepting the challenge, the duel between the swordsman Sirius and the King began within the confines of Polaris’s barrier.