Rasal, who had become Isis’s subordinate through a series of unexpected events, was currently visiting the Great Library Isis had told her about. She had been granted permission to read any book she liked, and as she gazed upon the staggering number of volumes, she couldn't help but mutter to herself.
"...Splendid. It is truly no exaggeration to say that every kind of book imaginable is gathered here. Since my years of research have only just concluded, perhaps I should search for a new theme. Gaining access to this much reference material might actually make becoming a subordinate worthwhile."
After glancing through several books while whispering to herself, Rasal let out a deep sigh.
"Still, to leave me entirely unmonitored... is it truly wise to be so lax?"
Checking a few more titles while lost in thought, she decided it would be best to familiarize herself with the rest of the castle. She stepped out of the Great Library and began walking down the hallway.
Before long, an insectoid demon with six swords strapped to her waist—Sirius—approached from the opposite direction.
"Hm? You must be the one who recently joined our ranks..."
"Hmm? Ah, you are also one of Isis-sama's subordinates. I am Rasal Marfik."
"I am Sirius. A pleasure to meet you. It must be some twist of fate that we crossed paths here. I was just about to head out for training; would you care to join me?"
"...I see."
Sirius proposed the idea with a faint smile. To put it simply, it was an invitation to a mock battle to gauge each other's strength.
(This is perfect. I haven't had a chance to test the results of my research in actual combat yet. From the looks of her, she seems to be quite the powerhouse. She should be a worthy opponent.)
Recognizing that Sirius possessed strength close to her own, Rasal saw her as the ideal partner to test the fruits of her long labor.
"Very well. I was also feeling the urge for a bit of combat."
"Then it's settled. Let's head outside. Polaris-dono has prepared a barrier for us to use."
The two reached an agreement, and the mock battle began in a peaceful enough atmosphere... but as time passed, the mood took a sharp turn.
"Enough with these underhanded tactics! Face me fair and square, you coward!"
"Don't be an idiot. No matter the method, the one who wins is in the right. Simply charging forward with brute force makes you no better than a beast... why don't you try using your head for once?"
The two were fatally incompatible when it came to their combat philosophies. Sirius was a warrior who fought honorably on the front lines with her own body, while Rasal was a necromancer who stayed out of harm's way while her undead soldiers did the fighting.
As it turned out, they disagreed on almost everything else as well. Before long, their mock battle had devolved into a hostile, confrontational brawl.
"...Hmph. No matter how much you 'use your head,' there is no way I could possibly lose to someone who can do nothing but manipulate carrion."
At first, Sirius had been holding back because it was supposed to be a friendly match, but the concept of restraint had long since vanished from her mind. She manifested all six of her arms and unsheathed every single sword at her waist.
"A muscle-brained woman who can only push with force thinks she can defeat me? Kukaka! At least you have a sense of humor!"
Rasal had also been fighting with some degree of caution to test her research... but now, as if such considerations no longer mattered, she summoned a horde of undead soldiers that practically blotted out the horizon.
"...What?"
"...Hah?"
The two glared at each other, and a life-or-death struggle disguised as a mock battle was about to reach its climax.
"Drop dead, you carrion woman!"
"Get crushed, you muscle-brain woman!"
With those savage shouts, the two top-tier Count-class fighters were about to collide... or so it seemed.
"Cut it out already, you idiots! Drink this, Violent Beast! Apocalypse!!"
""Eh? Gyaaaaaahhh!?""
Before they could strike, a jet-black flash accompanied by a roar of fury flew into the fray, blowing them both away.
"You're brawling right next to Isis-sama's residence! Restrain yourselves to a level that Polaris's barrier can actually contain! What would you have done if you'd damaged the surroundings?!"
"I... I am deeply sorry."
"Ugh... indeed, I was somewhat lacking in consideration."
The two, who had completely overheated, were sent flying by Iris and subsequently forced to sit in seiza for a long lecture. Both seemed to realize they had gotten carried away, and they wore expressions of genuine reflection as they listened.
After grumbling at them for a while longer, the lecture finally ended. Sirius and Rasal looked at each other with sullen, dissatisfied faces.
"...Well, I will at least admit that you have the strength to back up your arrogance."
"...Likewise. I acknowledge that you possess an exceptional intellect and strategy."
Somehow, they seemed to have recognized each other's prowess after all. Though their words were sharp, they offered a begrudging form of praise to one another.
"Still, if we had been allowed to continue, I would have been the winner."
"The only tragedy is that the interruption prevented me from seeing the unsightly image of an insect woman rolling in the dirt—a sight I'm sure I would have enjoyed in just a few more moments."
"...Hah?"
"...Ah?"
Reacting to the simultaneous claim that "I would have won if we'd continued," they immediately began clashing their magic power and glaring at one another again.
"...You two... if you're going to keep going, stay within the limits of the barrier. Are we clear?"
"So she says. How lucky for you; you've escaped with your life."
"Yeah, let's head back to the barrier then. Don't worry... I'll make sure to go easy on you this time."
"...Hah?"
"...What was that?"
"...You two, depending on your next words, I might just blow you away again."
Watching the pair continue to provoke each other with such aggressive attitudes, Iris let out a long, weary sigh.
Serious-senpai: "Well, when it comes to these two, it's probably less that they're truly on bad terms and more of a 'the more you fight, the closer you are' kind of dynamic."
???: "In the Mutsuraboshi spin-off stories, they're often shown cooperating on various tasks, so that's likely the case."