Since being granted Hippolyta's axe and the Mageblade of Light, Kay's training had truly entered the next level of hell.
It wasn't about brute strength, but the delicate art of reading the flow of mana and applying primal runes at precisely the right moment.
It was one night during the endless, bone-shaving training that paused for neither day nor night.
"Ugh… every joint in my body is throbbing."
Kay, drenched in sweat, stepped out beyond the castle wall.
He wanted to escape Tamamo's clingy flirtations and Medusa's furtive glances, cool off for a moment, and breathe the night air in peace.
The nights in the [Abyssal Realm] were always chilly, the air carrying a faint scent of iron filings mixed with the stench of demonic beasts' blood.
With no destination in mind, he walked along the outskirts of the Shadow Forest, bathed in ashen moonlight—then his footsteps faltered.
A familiar silhouette sat perched on the ruins of a shattered ancient relic up ahead, staring blankly at the sky.
It was Jeanne d'Arc Alter, her black cloak billowing in the wind.
Gone were the venomous eyes and irritated look she usually bore. Hugging her knees, her small back appeared peculiarly desolate in this vast, silent [Abyssal Realm].
"Jeanne?"
"…Ah! Wh-What the—?! You didn't even make a peep!"
Startled by Kay's call, Jeanne d'Arc Alter bolted upright, clutching the pitch-black banner she always kept at her side in a defensive stance. Yet her eyes betrayed a rare hint of embarrassment.
"Sorry if I startled you. I was out for a walk alone. Why aren't you asleep and wandering out here? Aren't you cold?"
Kay paid no mind to her sharp reaction; he strolled over and perched himself on the rock beside her.
At the suddenly reduced distance, Jeanne d'Arc Alter flinched and pouted, her body trembling.
"Hmph, Servants don't feel the cold. And that castle's too noisy to get any sleep. Every night you make such a ruckus outside your chamber—like a bunch of animals in heat. I got annoyed and came out for some air, alright? Why else!"
In truth, she'd fled because the sounds drifting from Kay's room set her nerves aflame with an unknown vexation, but she'd never admit that.
"Ah… Uh, sorry about that. It just… got out of hand."
Kay scratched the back of his head sheepishly.
A moment of awkward silence passed between them. Despite the chilly night in the [Abyssal Realm] and no fire in sight, a faint warmth radiating from Kay's large frame brushed gently against Jeanne d'Arc Alter's skin.
"…Hey."
After a short silence, Jeanne d'Arc Alter was the first to break it, her gaze fixed on the night sky.
"So… you're really planning to go back to Britain, huh?"
"Of course. My siblings and my nieces are there."
"That's just stupid."
Jeanne d'Arc Alter hugged her knees tighter and snapped in a sharp voice, her tone trembling slightly at the edges.
"What guarantee is there that they'll still be waiting for you? Humans are creatures that betray. They forget favors and, when they deem someone unnecessary, burn them like they were never important—that's the essence of those worthless scumbags."
That was her own story.
The harrowing memory of Saint Joan of Arc being betrayed by those she risked her life to save, then burnt at the stake.
Even if she wasn't truly Joan, that memory was as vivid as ever.
She projected that terrible wound onto Kay's situation.
"Even if you return there after all this backbreaking effort, they might have already forgotten you. Hell, they might even throw stones at you when they see you. Isn't that right? Even the taste you cooked for them will fade with time."
In her voice was not so much hatred for the world as a primal fear of being hurt again.
She didn't want to see Kay get hurt. So she urged him to expect nothing. It was her own clumsy, twisted form of comfort.
Kay stared silently at her face, framed by the night breeze.
Her features were the spitting image of his sister's. Yet her soul was more fragile than anyone's, curled up like a hedgehog bristling with quills.
"…Maybe you're right."
At Kay's understated reply, Jeanne d'Arc Alter snapped her head away.
"See! I told you! So it's just a pointless waste of effort…"
"But… I'm still going back."
Kay looked up at the night sky and offered a faint, yet infinitely warm, smile.
"I won't deny that humans betray. I've rolled around in the dirt long enough to know that. But listen, Jeanne—I'm no saint or hero. I didn't cook for them expecting anything in return or praise."
"I don't care if they forget how my cooking tastes. Fine if they call me a monster and throw stones. I just… want my family, the ones I love, to be fed, warm, laughing under a roof. Even if I get hurt, as long as that life continues, my life is still in the black. The responsibility of a head of a household is, by nature, a foolish, unprofitable endeavor."
"…You, really."
Jeanne d'Arc Alter was at a loss for words.
No Avenger's logic, fueled by vengeance against the world, could refute this man's blind yet humble altruism.
It wasn't the grand humanitarianism of a saint, but a deeply personal, almost earthy love scented with soil and cooking.
"And above all… I like you, Jeanne."
"…W-What?!"
Jeanne d'Arc Alter's pale cheeks exploded into scarlet at the sudden emotional blow, her eyes darting in panic.
"Y-You, what nonsense are you spouting all of a sudden?! Are you insane?!"
"It's not nonsense. I know exactly how soft you are under all that grumbling."
Kay smirked and scooted another few inches closer to her.
"You—though you rage about burning everything to ashes, you're a pro at adjusting the flames when I cook. You nail the temperature so the outside gets crisp and the inside stays juicy. Thanks to you, cooking has become way easier these days."
"W-Well, that's just… I was tweaking the heat because I'd get annoyed if the meat tasted bad! Don't get the wrong idea!"
"Fine, let's say that. Still, thank you. I'm glad you're here. Keep watching my back from now on, okay?"
Kay reached out his hand.
His large, scarred, yet warm hand dropped softly onto Jeanne d'Arc Alter's head.
Then, gently, he stroked her soft hair.
"…Ah."
Jeanne d'Arc Alter's shoulders twitched.
The moment Kay's warmth touched her, the loneliness and hate frozen to her bones felt as though they melted away.
It was a familiar, affectionate touch—like something he'd give to a younger sister.
But to Jeanne d'Arc Alter, that hand was an unquestioning affirmation and warmth she'd never experienced before.
"…This is annoying. That dope who only knows cooking… why is my heart racing like this? I feel like I'm going mad."
She couldn't bring herself to look up, burying her forehead deep in her knees.
"…Do whatever you want, idiot."
That mumbled reply was the only form of rebellion she dared muster.
That awkward night walk became the decisive moment when the tsundere fortress around her heart crumbled.
Much time passed afterward.
In the [Abyssal Realm], it felt as though a year had passed.
Every night, Kay endured torment from Tamamo, Medusa, and Scáthach, yet he still stole moments alone with Jeanne d'Arc Alter.
Whenever he cleaned his weapons, she would burn away impurities from the blade with her flames, and whenever he collapsed, exhausted from training, the one who tossed him a damp towel—grumbling all the while—was always her.
And finally.
One morning, when Kay lifted his heavy eyelids…
"…Hmm."
He saw someone beside him sleeping soundly, their breaths soft and steady.
The cumbersome black armor and cloak she normally wore were gone. Instead, draped only in a thin blanket, she lay naked, clutching Kay's solid bare chest—a dazzling vision in white.
"…Jeanne?"
Startled, Kay shifted in bed, and she snapped awake with a sleepy pout.
For a moment, her half-lidded eyes met Kay's alarmed gaze in the dim light.
"…!!"
Jeanne d'Arc Alter's pale face flushed crimson in an instant.
The memories of last night slammed into her like a storm—the moment she couldn't help herself, shoved everyone aside, and barged through the door into his chamber.
Her usual grumbling self was gone, replaced by the vivid memory of the entire night—her crying, clinging to his waist, demanding his affection alone.
"Hey, hey!! Look away! Shut your eyes!! I'll kill you, you pervert!!"
Panicked, she grabbed a pillow and pounded Kay's face with it, yelling at the top of her lungs.
"Ow! Stop! Yesterday you couldn't get enough of it, and now you start hitting me before breakfast?!"
"W-Who said I was clinging, clinging, clinging!! I only did you a favor out of pity, okay?! Don't get the wrong idea! I didn't do it because I like you—just… it was cold, so we shared some body heat!"
Jeanne d'Arc Alter wrapped herself tightly in the blanket and fled to the corner of the bed.
Yet her wriggling toes peeking out and her reddened neck laid bare how intensely she was aware of Kay.
Kay brushed aside the pillow with a chuckle and reached over the blanket to stroke her head.
"Alright, alright. Fine, we'll say it was because you were cold."
The tsundere had completely fallen.
With that, all three Servants were now bound to Kay—body and soul.
And as time passed, it came to the fifth year since they'd fallen into the [Abyssal Realm].
Kay stood in the middle of the ashen wasteland.
"Now, the time has come to return."
Having finally earned Scáthach's recognition of his strength, all that remained for Kay was to return to Britain.
Scáthach watched him with her back to the moonlight.
She didn't wear her usual rigid, imposing queenly stance. Her expression was strangely tender, and most of all, one hand was cradling her lower abdomen protectively.
"Kay."
"Huh?"
"You're going back to Britain now. You'll no longer lose against any knight or hero."
Scáthach slowly approached and took Kay's hand, placing it gently on her lower abdomen.
"…Huh?"
Kay's eyes widened.
Through her rock-hard abs, he could feel a subtle yet unmistakable pulse.
"Scáthach… this can't be."
"It is."
Scáthach gave a faint smile.
"Inside me, your bloodline has taken root. Your life force pushed through the sacred essence of the Celts and sprouted—such tenacious vitality of yours."
"Pregnant… Pregnant? You?!"
Kay went dazed, as if he'd been struck in the head.
Confusion hit him before joy. Why reveal the pregnancy right before he was about to leave?
"Why… why tell me now? If you'd told me earlier…!"
"If I'd told you? You wouldn't have focused on training, you'd have been all jittery. And… you might have refused to leave because you'd want to stay with me."
Scáthach stroked Kay's cheek.
"Did you think I didn't know how damned kind-hearted you are? You cherish even unrelated younger siblings, but if you know your own child is being born, you'll never abandon me."
"…!"
Struck to the core, Kay couldn't utter a word.
Scáthach was right. He cherished those unrelated to him as family—how much more would he feel for his own flesh and blood?
His eyes wavered in uncertainty.
His siblings and Gareth waiting in Britain. And Scáthach, who would be left alone to give birth in the [Abyssal Realm].
"Scáthach, I…"
"Don't waver."
Scáthach squeezed Kay's hand firmly.
"I am the Slayer of Gods and sovereign of the [Abyssal Realm], Scáthach. Did you think I'd fear giving birth alone like a mere human woman? On the contrary, this child is the strongest guarantee and blessing to ensure your safe return to Britain."
She looked Kay directly in the eyes.
"Go, Kay. Go reclaim the life you fought to protect. On the day you return a man unashamed to be this child's father, I will gladly place this child into your arms."
As a mentor, she could not stand in her pupil's way.
Before her noble resolve, Kay swallowed the flood of tears threatening to spill and nodded.
"…All right. I promise to live, become a great dad, and come back for you."
Kay knelt carefully and pressed his face against Scáthach's belly.
"On one condition—let me name this child."
"Very well. What will you name them?"
"…Uersaha."
Kay murmured softly.
"Uersaha… A strong and beautiful name. I like it."
Scáthach brushed a strand of hair from Kay's brow and smiled gently.
Tamamo would have had a lot to say, but for now, she remained silent.
Then, a massive dimensional gate opened in the sky of the [Abyssal Realm].
It was a swirling channel of mana connecting to Britain.
Kay stood before the gate with the golden axe slung over his back and the Mageblade at his waist, alongside his Servants.
When he looked back, he saw Scáthach watching him with her arms crossed.
"…I'll be back."
Kay gave a firm nod and plunged into the vortex of light.
Five years of training in the [Abyssal Realm].
He pushed his ordinary body to its limits, alongside three Servants and legendary arms, and left his bloodline behind in the [Abyssal Realm].
And knowing he could never return to the [Abyssal Realm], he still returned to Britain.
Without witnessing the birth of his child, he made his way home. For if he saw the birth, his resolve might crumble. And if he took the child with him, Scáthach would suffer eternal solitude once more.
Perhaps it was his gift and repayment to her—a family for the lonely, mightiest of witches.
"Farewell… you foolish husband."