Reuniting with My Little Sister Was a Disaster. Didn't Even Knock. Guess Mom and Dad Failed at Parenting.

"So... this is why you turned Yggdrasil's Sacred Grove into a warzone..."

This was the headmistress's office.

Azaria's voice trembled slightly as she addressed the two standing before her.

"That bastard was defiling the World Tree—!! How could you let some outsider like this in?! What the hell were you thinking—!!"

Touka, the S-rank Magician, was practically steaming, her face red with fury as she shouted at Azaria.

"Quite the mouth for someone I just met. I was merely communing with the tree."

Scratch, scratch.

Behind her, the Black Knight dug at the inside of his helmet's earhole with a finger as he retorted.

"People don't call it 'communing' when you force yourself on something... There's a separate term for that—rape."

Eileen stared at him with dead eyes.

"Does a tree even need human rights?"

"You don't seem to need them either."

Eileen, shedding every ounce of her usual shyness, shot back without hesitation.

"So, Headmistress. You'd better explain this guy to me."

Tap.

Touka jabbed a thumb toward the Black Knight. Azaria smiled faintly and began.

"Where to start... A month ago, the ultra-hazardous Magic Soldier Gear sealed beneath the Garden—Angra Mainyu—was suddenly transported to Plutoid."

"Out of nowhere, with no warning...? And why Plutoid—?"

"Chaos broke out, of course. But then he possessed it and annihilated the Catastrophe in a single strike."

"..........!!!"

Whoosh.

Touka whipped her head around to stare at the Black Knight.

"Since then, he's been single-handedly slaying every 'Disaster' that's emerged in Stardust. Even the mayor acknowledged his strength."

"That's... bullshit—!"

Crack.

Touka clenched her fists, disbelief dripping from her voice.

"After that, we were put in charge of overseeing him. He'll be staying here for a while, so how about a proper introduction?"

BAM—!!!

"I refuse—!!!"

Touka slammed both hands on the headmistress's desk, her scream shaking the room.

"You expect me to believe the mayor endorsed some arrogant bastard coasting on borrowed power?! Why the hell would he—?!"

Her eyes burned with a volatile mix of rage, unease, and frustration.

Azaria studied her for a silent moment before answering.

"Because it isn't borrowed power."

".......!!!"

"I'll admit, I've never liked the mayor, but no one in this world has a sharper eye for talent than him."

"I'll see for myself."

RUMBLE—!!!

In an instant, dark magic erupted from Touka's body, swirling into a violent storm that tore through the air.

"Eeek—!! Headmistress—!!"

Eileen scrambled behind Azaria in terror.

Crack—crack—crack—!

The floor splintered under the pressure, and loose papers floated into the air as if crushed by an invisible force.

Whoosh—whoosh—whoosh—

"Touka."

Azaria's voice dropped low ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠in warning.

"Fight me. Right now."

Touka's glare was lethal as she commanded ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠the Black Knight.

"Go fuck yourself, bitch."

Screeeech—!

"If you're really an S-rank Magician...!!!"

At the brink of explosion, Bella burst through the office door.

"Uh..."

She froze under the suffocating tension.

"I'll... just go..."

Screeeech.

She immediately backpedaled.

Whoooooosh...

"Who was that?"

Touka, finally calming down, turned to Azaria.

"A friend who'll be staying with us—and with him—due to certain circumstances."

".......... A lot's happened while I was gone, huh."

Thud. Thud. Thud.

Touka gnashed her teeth as she stomped toward the exit.

Tap.

"You. Dueling arena. Tomorrow. 2 PM."

She stopped at the door, jabbing a finger at the Black Knight.

"No thanks."

"You'll show."

Screeeech. Slam.

As Touka vanished, the Black Knight turned to Azaria.

"What's that brat's problem?"

"She's obsessed with becoming a 【Disaster Slayer】. She just failed the selection again, so she's on edge."

"If you're her superior, shouldn't you beat some manners into her?"

The Black Knight spoke with the bluntness ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠of an older sibling. Azaria shook her head.

"No method I use will matter unless she lets go of that obsession herself. Which is why I have a request."

"....... Want me to beat her up for you?"

"Bingo~!"

"Fine."

"Eh...? Seriously?"

Azaria blinked at his immediate agreement.

"Was already planning to. Five weeks in a full-body cast should do the trick."

___. ___

"So... you're fighting that S-rank Magician?!"

"Where'd you pick that up?"

Bella plopped onto the bench where the Black Knight was lounging.

"Rumors are all over the Garden."

"Damn snitches."

"But how'd it even come to this...?"

"Probably because he picked a fight first."

Siv's sarcastic remark wasn't wrong.

"That bitch started it. A good beating cures heat. I'll fix her myself."

Crack.

The Black Knight flexed his fist confidently.

"You seem... weirdly excited?"

"A dream come true."

"Huh?"

"Punching that brat's face—my lifelong wish. Finally happening."

"Ugh... what's wrong with you...?"

Bella groaned at his enthusiasm.

___. ___

"Bella~! See you in class tomorrow~!"

"Later."

In just one day, Bella had already charmed half the student body.

Her natural friendliness and cool looks made her an instant hit.

But as she enjoyed her newfound popularity...

"Hey."

Tap.

"Huh?"

"We need to talk."

Touka appeared in the hallway.

"Uh... uh...? Is this about earlier in the headmistress's office?!"

"Just follow me."

___. ___

They stood before Yggdrasil.

"What do you know about that Black Knight?"

Touka had dragged Bella to a secluded spot to interrogate her.

"Wh-what's with the sudden—?"

"Talk."

Touka's glare was razor-sharp.

"I-I barely know him! We only met a few days ago—!"

"It's true. He was originally an underground fighting champion."

At Siv's input, Touka exhaled sharply.

"Tch... A bottom-feeding roach. Why would the mayor...?"

Kick—!!

She punted a stray branch across the ground.

"Um... are you nervous about fighting him—?"

"Don't be ridiculous—!!"

Touka's sudden roar made Bella flinch.

"Eek—!! Then why drag me into this—?!"

Bella wasn't one to stay quiet.

"Grr... I don't know—!! Just answer—!!"

"She's completely unreasonable."

"Shut up—!! You shut up—!!"

Touka snapped at Siv's jab.

(She's... kinda like the Black Knight...)

Bella kept that thought to herself—voicing it would only end badly.

"Whatever. I'll prove it with strength. Once I crush him, I'll take it up with the mayor."

Kick—!!

Touka stormed off, fuming.

"She's so self-centered..."

"What was that?!"

Touka spun around at Bella's mutter.

"N-nothing! Absolutely nothing—!!"

Bella gaped—her hearing was as insane as the Black Knight's.

___. ___

The next day. 1 PM.

BONG—!! BONG—!! BONG—!!

The bell tolled across the combat training arena.

"So, you're asking me to referee?"

"You're the only one who can keep up with my speed."

Touka had requested Subaru to oversee the duel.

"Hmm... I doubt he'll even show."

At Subaru's skepticism, Touka scowled.

"A real magician answers a challenge. Even that arrogant bastard wouldn't risk being called a coward."

BONG—!! BONG—!! BONG—!!

2 PM sharp.

"............"

"Told you."

No Black Knight.

BONG—!! BONG—!! BONG—!!

3 PM.

"Shall we look for him?"

"........... I'll wait longer."

BONG—!! BONG—!! BONG—!!

4 PM.

"Gyaaaaaaaah—!!! Why isn't he here—?! Is he even a real magician?!"

"Probably not, I'd guess..."

"Shut up—!! When I find him, I'll—"

BONG—!! BONG—!! BONG—!! BONG—!! BONG—!! BONG—!! BONG—!! BONG—!! BONG—!! BONG—!! BONG—!! BONG—!!

"BELLY-DANCING IS FUCKING LIT—!! YEAAAAAAAH—!!!"

"Uh..."

Touka paled as she looked up at the central tower.

BONG—!! BONG—!! BONG—!! BONG—!! BONG—!! BONG—!!

Because there, swinging his hips against the giant bell, was the Black Knight.

"How long has he been at it...?"

"This is almost impressive..."

The students watched in awe rather than disgust.

"Hey... didn't you have a 2 PM appointment?"

Bella yelled over the ringing.

BONG—!! BONG—!! BONG—!!

"The fuck you say?"

"I said—DIDN'T YOU HAVE A 2 PM THING—?!"

BONG—!! BONG—!! BONG—!!

"Can't hear you, bitch."

"STOP RINGING THE BELL, YOU PSYCHO—!!"

Bella finally snapped.

"Heh... hehehehehe..."

"Uh... Touka...?"

Subaru called out to her as she broke into ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠hysterical laughter.

"Right... Not a real magician. Of course not. Ahaha. AHAHAHAHAHAHA—!!"

"What kind of degenerate jacks off next to someone mid-bell-ringing? Raised in a barn..."

Whoooooosh...

".........!!!"

A massive shadow fell over the Black Knight.

"Oh for fuck's—"

KABOOOOOOOOOM—!!!!