By the time Kael Gremory turned five, the Gremory estate had mostly given up trying to understand him.
They couldn't detect his energy.
They couldn't track his movements.
They couldn't predict when he'd appear—only that he always did, right when it would cause the most confusion.
But lately, something had changed.
He wasn't just strange anymore.
He was smug.
Not arrogant—not loudly, anyway. But the way he walked into rooms now, the way he leaned just slightly when speaking to someone, the way he sighed dramatically before answering basic questions…
He radiated the energy of someone who knew the answers to tests no one else had studied for.
"Kael, dear," Venelana called from across the dining hall, "would you like more fruit?"
Kael, lounging on a chair like he was born into the role of mysterious prodigy, tilted his head without turning.
"Only if the grapes have been inspected by a council of woodland spirits."
Venelana blinked. "I… what?"
Sirzechs, seated nearby, snorted into his tea.
Kael sighed. "No, thank you, Mother."
He trained now, daily.
Not out of necessity, but for refinement.
Control. Precision. Style.
He had mastered short-range teleportation without leaving a trace. His cursed energy control was so delicate he could phase through locked doors and emerge the other side with his hair still perfect.
He didn't spar with practice dummies anymore.
He sparred with time itself.
Or so he claimed.
Ajuka dropped by occasionally to observe his progress. On one such visit, Kael greeted him midair—lying on an invisible platform of cursed energy like it was a hammock.
"You're floating again," Ajuka noted.
"I was meditating."
"Upside down?"
Kael shrugged. "The blood rushes to my sarcasm that way."
Ajuka grinned. "You're unbearable now."
"I've earned it."
Socially, Kael had started doing the devil noble equivalent of trolling.
When a visiting noble asked what his magic type was, Kael answered:
"I'm mostly flavored mist and spite."
When a child tried to challenge him to a duel, Kael paused, looked at him from behind the blindfold, and said:
"Only if we're fighting for control of the moon."
When a tutor asked what Kael wanted to be when he grew up, he replied:
"A concept."
The staff learned to stop asking questions. Mostly.
Only Grayfia remained immune to his trolling, routinely assigning him structured study hours and private sparring sessions with enchanted illusions.
Kael completed every assignment.
Not because he wanted to impress her…
…but because she was the only one who didn't flinch when he casually walked through walls.
He respected that.
That evening, Kael stood atop the Gremory tower, arms crossed behind his back, blindfold glowing faintly under the sunset.
He wasn't thinking about the future. Not exactly.
He was just… watching.
Waiting.
Amused.
And just a little curious to see how long the world would keep underestimating him.
Kael Gremory had developed a reputation among the Gremory tutors.
Not for misbehavior.
Not for laziness.
Certainly not for lack of ability.
No—his crime was being unteachable.
Every instructor assigned to him eventually came to the same exhausted conclusion:
"He already knows. He just won't tell you that he knows."
Take, for example, the morning's history lesson.
"Kael," the tutor said, clearly nervous, "can you tell me what sparked the civil conflict between the original Four Satans and the newer factions?"
Kael rested his chin on one hand.
"I could," he said slowly. "But that would rob you of the joy of discovery."
The tutor stared.
Kael raised an eyebrow behind his blindfold. "Also, Ajuka said to tell you that if this turns into a five-slide crystal orb presentation again, he's pulling your funding."
"…What?"
Kael sipped tea that hadn't been there a second ago.
To make matters worse (for everyone else), Kael's training had advanced beyond anything measurable by traditional devil standards.
The manor's magical sensors had started short-circuiting when he powered up.
Staff had begun referring to certain rooms as "Kael Zones" and avoiding them altogether during his sessions.
One such session happened that afternoon.
Kael stood calmly in the middle of the Gremory training hall. Grayfia watched from the upper balcony, clipboard in hand, taking notes like this was a court-mandated performance review.
"Begin," she called.
Kael raised a hand.
The cursed energy didn't explode.
It didn't roar.
It simply folded around him.
He vanished. Then reappeared twenty feet behind a target dummy, now turned to splinters.
Grayfia didn't react. "Sloppy entry vector."
Kael yawned. "It was a warning shot."
"To who?"
"The concept of being average."
After training, he passed by two younger noble children visiting for political exposure.
One asked, loudly and with far too much pride:
"Hey, aren't you the weird one with no magic?"
Kael turned, blindfold covering any expression.
He walked up slowly, stopped just short of their personal space, and tilted his head.
"Yes," he said gently. "But I compensate with personality."
The child blinked.
Kael continued walking without another word.
The other child whispered, "I think we lost."
Later that night, in his room, the gacha system chimed quietly.
"Daily Roll?"
Kael considered.
Not tonight.
"You're evolving. Becoming… tolerable."
Careful. I might develop humility next.
"Liar."
Kael smirked.
Outside, the Gremory estate glowed softly in the evening light.
Inside, Kael lay back on his bed, hands behind his head, and sighed.
Not out of stress.
Just to see if he still could.
Rias Gremory was now one year old.
Which meant she had developed just enough magical instinct to be dangerous—but not nearly enough self-control to care.
Kael, now six, had already cultivated the patience of a sage monk and the sarcasm of a retired war general. And lately, he was putting both to use.
"She's loud," he muttered one morning as Rias shrieked at a spoon that refused to float.
"She's expressive," Venelana corrected, not looking up from her embroidery.
"She just challenged the silverware to single combat."
Venelana sipped her tea. "It builds confidence."
Kael rested his chin in one hand. "So would not flinging cursed soup at her own reflection."
Venelana smiled serenely.
Kael stared at the ceiling and quietly wished for teleportation scrolls that could take him to another reality.
He didn't dislike Rias.
But she was chaos incarnate.
And Kael… valued peace.
More often than not, he watched her from a distance. Not out of fear—he had faced more cursed threats by age five than most adult devils ever would—but because her energy exhausted him.
There was something deeply unsettling about a toddler whose power surged every time she didn't get pudding.
She was a phoenix in the making. Unfortunately, she acted like one that had skipped nap time.
One memorable day, she attempted to fly off the balcony with a napkin tied around her neck like a cape.
Kael caught her midair without looking, gently lowered her, then sighed.
"That's not how flight works, little flame."
She giggled.
Then immediately tried again.
Sirzechs visited that afternoon.
Radiant. Confident. Looking like a walking advertisement for magical hair conditioner.
Kael met him at the front gate, arms crossed and unimpressed.
"You're late," he said calmly. "Rias has already declared war on two chairs and a houseplant."
Sirzechs blinked. "She's one."
"She's a Gremory."
Sirzechs chuckled. "Fair enough."
As they strolled through the estate's west wing, Sirzechs spoke of diplomacy and battle formations, of noble tensions and upcoming evaluations.
Kael nodded periodically, sipping tea from a porcelain cup engraved with the words "I'm listening. Probably."
Rias spotted them halfway through the hallway and screamed "BAAAHH!" before charging at full speed.
Kael, without hesitation, stepped out of the way.
Sirzechs caught her just in time, spinning slightly from the impact.
"She's developing tackle form," Kael muttered. "I recommend reinforced robes."
Later, the three of them sat in the courtyard. Rias babbled nonsense while poking Sirzechs' face. Kael lounged nearby, watching the garden lanterns flicker to life.
"So," Sirzechs asked, "how's training?"
"Efficient," Kael replied. "Controlled. I've stopped scaring the help."
Sirzechs smirked. "Voluntarily?"
Kael sipped. "They tremble when I smile. I consider that progress."
Grayfia arrived on cue.
"I understand you've modified the magical locks in the library."
Kael gave a small, satisfied nod. "Too many people reading the wrong books."
"They scream now."
"Only when judged unworthy."
Grayfia paused. "The scream quotes philosophy."
"I have range."
Sirzechs turned away, pretending to admire the clouds so Kael wouldn't see him laughing.
That evening, Kael stood alone on the manor roof, the world silent beneath a canopy of stars.
He could still sense Rias from inside—her power flickering like a candle trying to burn the table.
She was a storm.
He was a wall.
He didn't hate her.
But peace was a fragile thing…
And she was a natural disaster in a pink dress.
It began with a polite letter.
House Sitri requested a social visit—nothing political, they said. Just a gesture of goodwill between noble families. A chance for the children to meet. To build early friendships.
Kael Gremory knew better.
No noble ever asked for "just" anything. And nothing about diplomacy between Great Houses was ever casual.
Still… he agreed.
Mostly because he was curious.
And a little because he liked watching nobles squirm when faced with his casual sarcasm and unpredictable mood shifts.
The Sitri family arrived precisely on time, as expected.
Lord and Lady Sitri were dignified, warm, and composed. They walked with grace. They smiled with sincerity.
Their daughter—Sona Shitori—was just a baby, no more than a year old.
Kael stood at the estate's entrance, arms folded, blindfold perfectly in place.
When Lady Sitri stepped forward to greet Venelana, Kael tilted his head and said evenly:
"Please don't worry. The Gremory teacups haven't exploded since last month."
Lady Sitri blinked.
Venelana sighed quietly through her nose.
While the adults moved to the formal sitting room, Kael lingered by the doorway, quietly watching Sona.
She sat calmly in her mother's arms, not babbling, not flailing—just… watching.
Her aura was faint, but precise.
Composed.
Disciplined.
It was strange seeing that kind of restraint from a one-year-old.
Kael, six years old and thoroughly jaded by his own sibling's weekly rampages, raised an eyebrow behind his blindfold.
This one might actually be tolerable.
The formal tea began slowly.
Venelana and Lady Sitri exchanged light political chatter. Zeoticus and Lord Sitri discussed recent magical developments. Sirzechs sat to the side with Rias in his lap, playing peekaboo with an enchanted napkin.
Kael?
Kael sat across from Sona, completely silent, sipping cursed tea from a cup labeled "This Is My Patience."
He didn't speak.
He didn't need to.
Sona, still nestled in her mother's arms, stared directly at him the entire time.
Halfway through the meeting, Lady Sitri noticed.
"She's… quite focused on you, Lord Kael."
"I get that a lot," he said calmly.
"She doesn't usually react to strangers."
"Maybe I'm not strange enough."
That earned a subtle chuckle from Lord Sitri and a not-so-subtle sigh from Venelana.
Rias, meanwhile, attempted to eat her napkin.
Kael leaned sideways and whispered to Sirzechs, "You're losing the war."
Sirzechs grinned. "You've met your match, haven't you?"
Kael stared at Sona again.
She blinked.
He blinked back—well, probably. No one could tell with the blindfold.
By the time the Sitri family prepared to leave, Rias had fallen asleep on Sirzechs' shoulder, and Sona had still not broken eye contact with Kael.
Just before they departed, Lady Sitri leaned down and said softly, "She's never looked at anyone that long before. What do you think it means?"
Kael paused.
Then answered, completely deadpan:
"Either she respects me… or she's planning something."
Later that night, Kael stood in the courtyard, arms folded, the night wind brushing softly through his silver hair.
"She's quiet," he murmured to himself. "Sharp."
The gacha system stirred faintly.
"Jealous? She might out-troll you someday."
Kael smirked.
"Let her try."
The Sitri visit had ended.
But something had shifted.
For the first time, Kael felt like he'd encountered someone who wasn't actively trying to impress, overwhelm, or outshine. Sona Sitri had simply… observed him.
And while Rias continued to wage chaotic war on the concept of peace, Kael's mind kept drifting back to the calm-eyed baby who stared at him like she was trying to read his entire soul.
The next morning, Kael was found floating upside down in the hallway outside the dining room.
Grayfia paused, stared, and asked in the flattest voice she could manage, "Why?"
Kael, hands behind his head, slowly rotated upright.
"Perspective," he answered.
Sirzechs passed by behind her and added, "It's either this or he animates the chandeliers again."
Kael shrugged. "Still might."
His teleportation had also evolved.
Now he didn't just vanish from rooms—he slid out of reality, like space had quietly agreed to look the other way for a moment.
The staff stopped reacting.
The nobles learned not to flinch.
And Rias, now toddling everywhere like a miniature tyrant, began to look for him constantly, only to be outpaced by his casual dimension-hopping.
It became a quiet game between them.
She'd yell. He'd disappear.
She'd scream. He'd reappear behind her.
"Boo," he'd say, completely calm.
She'd scream again.
Later that week, Venelana received a thank-you letter from Lady Sitri.
It was polite. Respectful. And included a short line at the end:
"Our daughter hasn't stopped looking at the Gremory family crest since returning."
Venelana smiled and showed the note to Kael.
He read it once, then folded it carefully and tucked it into the inside of his coat.
No comment.
Just a smirk.
That night, Kael stood on the roof again, floating a few inches above the tiles without even thinking about it. His cursed energy shimmered faintly around him like heat rising off stone.
He traced invisible shapes in the air.
Nothing dramatic. Just quiet focus.
Behind him, the gacha system chimed.
"You starting a rivalry already?"
Kael raised one eyebrow. "I'm six."
"Exactly. That's late in the devil world."
Kael exhaled through his nose. "It's not a rivalry."
"You sure? She stared at you like she knew your browser history."
"…I don't have a browser."
"You will."
As stars blinked above the Underworld, Kael hovered silently in the cool night air.
The world was already growing noisy.