Time passed since my talk with Koneko-chan back at the main residence, and today marked the final day of our training in the Underworld.

“Uoooooooh!!”

BoostBoostBoostBoostBoostBoostBoostBoost!!

My power surges in an instant! I’m in my Balance Breaker state, diving into the final phase of training—a grand finale.

“Tannin! Don’t underestimate me now!” I shout.

“I know!” he roars back.

Boom! Boom! DOOOOOOM!!

My fists clash fiercely with Tannin’s in the sky. We’re both dead serious, our auras colliding, sparking wildly.

“Don’t forget about me!” Tiamat, back in her true form, throws a punch from the side.

I catch it head-on!

“Taking that straight-on? Impressive!” she says.

“Nah, I’m just getting started!” I yell.

Alright, Ddraig, full power!

Understood!

My aura swells, sparking around me. “Balance Breaker, Second Layer Zwei Phase—Tenbu Xenon!!”

My armor evolves, sprouting boosters on my arms, shoulders, and legs—my ultimate form! But I’m pushing even further today.

“Promotion: Rook!!”

My piece shifts, boosting my attack and defense.

“Is that your all, Issei Hyoudou? Quite the show!” Tannin bellows.

“It’s the last day, so I’m going all out, old man!”

“Interesting! Then I’ll match you with everything I’ve got!”

Their auras crank up a notch—Dragon Kings, huh? I’m not losing!

Accel Booster!!

BBBBBBBBBBBBBBBBBBBBBBoost!!!!

I blast aura from my boosters, charging Tannin. Dodging his fist, I land a punch.

“Guh!” he grunts.

With Tenbu Xenon and Rook’s power boost, that hit had to hurt, even for him! I move for a follow-up, but Tiamat’s magic barrage blocks me. I back off, keeping distance.

“I told you not to underestimate him, Tannin,” Tiamat says, standing beside him.

Tannin scratches his head, chuckling. “I didn’t mean to, but…”

“Hmph,” Tiamat sighs. “Issei’s at Demon King level now. That form’s burst power surpasses even us. That hit would’ve damaged anyone.”

“Yeah, this generation’s Red is something else…” Tannin opens his maw, unleashing a massive flame breath.

Oh, crap! His full-on breath? That’s no joke!

And Tiamat’s layering magic circles!? “Here’s more, Issei!” she calls.

Both Dragon Kings hitting me with a combo!? Are they trying to kill me? The scale’s too huge to dodge!

Damn it! Bring it on!

I channel aura into my right hand, thrusting it forward.

BBBBBBBBBBBBBBBBBBBBBBoost!!!!

“Uoooooh! Screw it, take this! Agni!!!” I roar.

My aura torrent, Tannin’s breath, and Tiamat’s barrage collide—

DOOOOOOOOOOOOOOOM!!!!

A massive explosion rocks the Gremory territory’s skies.

Twenty minutes later…

“Man, I thought I was gonna die…” I pant, sprawled on the grass alongside Tannin and Tiamat.

“To push back our attacks… Terrifying,” Tannin mutters.

“I didn’t expect him to go that far,” Tiamat adds.

You guys attacked like lunatics! Look, the terrain’s completely reshaped! Good thing no one lives nearby…

If the Gremory folks get mad, we’re all in this together.

Ugh, my arms and legs are killing me…

“Geez, you two could’ve gone easier. It’s the last day, and I nearly died,” I groan.

“What’re you saying? Holding back against you in that state would’ve gotten us taken out. Even full-on, winning’s not guaranteed,” Tannin retorts.

“Exactly,” Tiamat agrees.

Ugh, even Tiamat’s piling on. I’m too tired to argue…

“Let’s head back… Ow, ow, ow…” I wince.

Tenbu Xenon’s usage time extended, but I’m wiped out afterward. Better than last time, though.

“Don’t push yourself, Issei. I’ll carry you back,” Tiamat says.

Man, that’s a relief. Tiamat’s got my back.

As I’m touched by her kindness, she crouches, back to me. “Hop on.”

“H-Huh!?” I stammer.

“What’s wrong? Embarrassed?” she teases with a sly grin.

“Well, yeah…”

“Hahaha! The strongest Red Dragon Emperor scared of a piggyback?” Tannin laughs.

It’s not about being the Red Dragon Emperor! I’m a high schooler—getting carried by an older woman is mortifying!

“Issei’s got a cute side! Come on, hop up,” Tiamat urges.

“I said no!”

“Don’t hurry, and I’ll leave you here. That okay?”

Ugh… Walking twenty-plus kilometers to the residence in this state? Brutal…

Wait, Tannin’s right there! “Old man, help me out!”

“Sorry, kid. Pissing off Tiamat’s a hassle. Get on her back,” he says.

Betrayed by Tannin!?

In the end, I’m piggybacked by Tiamat back to the residence.

…I’ll keep it a secret that I fell asleep on her back.

At the Gremory residence…

“Well, I’m off. I’ll be at the Demon King’s party. See you there, Issei Hyoudou. And Ddraig,” Tannin says.

After Tiamat carried me back, it’s time to part with Tannin, who’s heading to his territory.

“Thanks for everything, old man.”

Sorry, Tannin. Catch you later, Ddraig says.

“I had fun. Never thought I’d train Ddraig’s host with Tiamat. Long life’s worth it. Wanna ride my back to the party?” Tannin offers.

“Really?”

“No problem. I’ll bring my familiars and swing by. Tiamat, you coming?”

“No, I’ve got plans. I’ll pass,” she replies.

“Shame. Well, Issei, later!” Tannin flaps his wings and vanishes into the sky.

I wave him off… from Tiamat’s back.

Come on, let me down! She’s in human form now, so I’m just a high school guy on an older woman’s back—embarrassing!

“I’m heading out too. Ajuka called me,” Tiamat says.

“Ajuka? What’s up?”

“We go way back. I help with his work sometimes.”

Huh, didn’t know that.

I climb off her back. “Thanks for everything. Say hi to Ajuka for me.”

“Will do. Later.”

Tiamat deploys a magic circle and teleports away.

Now… “Kiba, keep what you saw to yourself,” I say without turning.

I hear a surprised voice. “I thought I hid my presence,” Kiba says, stepping out from behind a building with a wry smile.

“You’d need to erase your aura completely to fool me. Looks like you’ve powered up a lot,” I note.

Kiba’s aura is denser, calmer—way stronger than before. That’s Kiba for you.

“You look beat, Issei-kun. What happened?” he asks.

“Was fighting two Dragon Kings until just now…”

“…Good work. Need a shoulder?”

“…Please.”

As Kiba supports me toward the residence, I sense another presence. Kiba turns too.

It’s… a mummy wrapped in bandages.

“Hey, Issei, Kiba! Been a while,” it says.

“Only you’d do something this crazy, Xenovia,” I say.

“What happened?” Kiba asks cautiously.

Xenovia glances at herself. “Trained, got injured, bandaged up, got injured again, bandaged again… and here I am.”

“You’re practically a mummy!” I exclaim.

“Rude. I’m not planning to be preserved forever.”

“That’s not what I meant!”

Man, her cool image from when we met is long gone. Her training’s paid off, though—she’s gotten way stronger.

“Issei-san, Kiba-san, Xenovia-san! Welcome back!” Asia calls, stepping out of the residence in her nun outfit. Yup, that’s the Asia look.

“Welcome back, you three,” Miu follows, in casual clothes. Makes sense—she’s supporting Gasper, so no need for a uniform.

“Hey, I’m back,” I say.

“Your clothes?” Miu asks.

“Burned to ash hours ago,” I reply. Tannin’s breath torched my jacket.

“You’ll catch a cold. Put something on,” Asia says.

“Yeah, I’ll change after a shower.”

After training outside, me, Kiba, and Xenovia shower, change, and gather in my room. Why my room? Apparently, it’s the easiest spot. Someone suggested Buchou’s room, but she flat-out refused—”Absolutely not!” Wonder what she’s hiding…

Anyway, we’re sharing training updates. Kiba talks about his master’s training, Xenovia about mastering Durandal, and I recount my Dragon King battles. Everyone’s floored.

Yeah, I figured they’d react like this. I mean, we reshaped the Gremory territory’s map. Several mountains got obliterated.

“Buchou, I’m really sorry…” I say.

“It’s… fine. That area’s empty. As long as you’re safe…” she replies, her smile strained.

Don’t look so horrified, Buchou! I wanted to keep it chill, but two Dragon Kings came at me full force! I had to go all out to survive!

…Seriously, I’m sorry.

“So, what results did you get?” Azazel-sensei asks.

“I figured out which piece suits me best with Promotion, extended Tenbu Xenon’s usage time, and the muscle pain afterward’s gotten better,” I say.

“As expected,” Azazel says. “But your training was too intense. The town heard the crashes this morning.”

Seriously? Tenbu Xenon amped things up. Sorry, town folks…

“Well, that’s it for today. Meeting’s over. Issei’s at his limit—let him rest before he collapses,” Azazel says.

He’s right. I’m exhausted and sleepy…

“You’ve all pushed hard these two weeks. Rest up, got it?” Azazel adds.

We nod, and the meeting ends. Everyone leaves my room except Miu.

“Miu… I’m gonna crash…” I say.

“Sleep well, Onii-chan. Great job training,” she replies.

I dive into bed and pass out.

Source: Webnovel.com, updated by NovelKeep