The young man and the tall woman stood in a bathroom clouded with white steam. Both were naked, brushing their teeth in front of the mirror.
“Freya, I’m gonna be honest with you.”
“Hmm?”
“This damn body is telling me to mate with you…”
“Because of me, Your Highness?”
“If I were a machine, my body would be flashing red right now.”
Fury’s body was burning—his physiological responses fully activated. His chest pumped blood throughout his system, and his member had swelled by pure instinct. And yet…
“That’s weird. Why don’t I feel anything?”
“Maybe because your body doesn’t find mine attractive.”
“Ehh…”
If a human were suddenly swapped into the body of a cow, they probably wouldn’t look at a female cow and think she was sexy—no matter what hormones or instincts were firing.
That’s what Fury felt too.
The mind of a Diablo was one thing. But the human male body he now wore was sending its own signals—signals his Diablo perception couldn’t quite connect with… not yet.
But it would, eventually.
Don’t worry. That’s how it is at first. Before long, your Diablo mind will sync up with your human body.
—Everton, Fury’s younger brother
“I need to find Casca before my mind syncs with this body…”
“Exactly, Your Highness… Same with me. I know if I get pregnant, I’ll be stuck for nine months… but if our minds sync up before that, there’s no guarantee we’ll be able to resist.”
“I have to resist. I made a vow to my wife.”
Diablos were encased in armor-like skin. In Fury’s true form, there wasn’t a single soft spot on his body—except for his eyeballs.
“Human bodies are so soft. And so slippery when wet.”
Freya’s true form had soft, slippery areas too—namely, her torso down to her legs—but they weren’t smooth like human skin. More like the slick, sticky surface of a salamander or toad.
So it wasn’t surprising she was fascinated by it.
Fury scrubbed his teeth in the mirror, gazing at his reflection with fascination.
“Human bodies are so easy to clean. No joints, no exoskeleton—just smooth comfort. It’s been a while since I got this body, and I’m still not over it.”
They both spit and rinsed, then wiped their faces and stepped out of the bathroom together.
Today was important: they were going to submit their application forms to take the entrance exam.
“Hold on, Freya.”
The young man grabbed his bodyguard’s hand before they stepped out.
He raised his hand and made a little “clawing” gesture with two fingers.
Freya did the same, and they practiced saying their lines in unison:
“We’re from the Kingdom of Zentinel. We’ve got a bit of strength and a dream of becoming knights. We’re here to apply for the entrance exam at Artheris. Nice to meet you, sir/ma’am!”
“Okay, that works.”
From now on—
Fury would go by Dan Burn.
Freya would be ZEEDEE Lamb.
Their human identities would be separate from their true selves. Each time they transformed back and forth, the names would change accordingly.
Let’s rewind for a moment, back to the day Fury and Freya underwent the ritual to obtain human forms.
The reason they could transform into humans… was thanks to knowledge seized from the Shadow Kingdom.
The Diablos had managed to capture some of the Shadow Kingdom’s knowledge before it was completely destroyed.
Only 30% of it had survived.
Among it was the ability to transform into other species.
Of course, humans weren’t the original target of this transformation spell. The Shadow Kingdom had been trying to turn themselves into Diablos—the Anomaly demons of this world.
No one knows if they succeeded. No spellbook containing that secret was ever found by military units.
But they did find the method to become human—which was valuable for any race physically stronger than humans.
That discovery led the Diablo emperor to a chilling realization: what if some Shadows had escaped the purge by transforming into humans?
Everyone agreed—it was possible.
The Shadows were not completely extinct. This discovery proved they could assume human forms.
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Which meant they could now be scattered, either plotting revenge or simply hiding.
That truth was unsettling—but also comforting in a way, because every known royal family member from the Shadow Kingdom had already been wiped off the record.
If they were to build an army for revenge, it wouldn’t be anytime soon.
Before Fury, several Diablos had already undergone transformation trials. They were spies—agents of the emperor—sent to infiltrate other kingdoms.
Espionage was essential. Intelligence gathering couldn’t be overlooked. War had taught the Diablos that knowledge was power—know your enemy, win a hundred battles.
True, the treaty said they shouldn’t interfere. But that’s what spies are for—they’re not supposed to get caught.
You could say the emperor broke the rules first.
But in reality… it was the only way for their island nation to survive.
Even humans had ships passing by the Diablo islands regularly. They only observed from afar, but it meant they were watching.
The transformation ritual required massive resources—rare materials and precious minerals.
Fortunately, the Diablos controlled the largest mana crystal mine in the world.
Yes, you heard right—a race that could barely use magic possessed the most valuable magical resource on the planet.
The irony was rich.
But it allowed Diablo to survive by exporting mana crystals, which were in constant demand.
And if Fury, the crown prince, was the emperor’s military aide—
Then the middle prince, Everton, handled commerce—specifically, managing those mana crystal exports. It’s why he’d always had the instincts of a merchant.
As for the youngest princess, Fiorentina—we’ll save her story for another time.
“To complete the transformation ritual, we need 1,000 tons of mana crystal… which comes out to 150 million credits, big brother. Two people means 2,000 tons. That’s 300 million credits.”
“Give me the summary.”
“Three hundred million credits could fund an entire kingdom for a year without lifting a finger. And I’m charging that debt to your account.”
“Hey, wait, what!? Freya’s going too!”
“Freya has to go—it’s her job to protect you. You, on the other hand, are going for personal reasons. Nothing to do with the kingdom.”
“Then cut the cost! I’ll go alone. That’ll slash the budget in half.”
“Big brother, you’re royalty. You can’t just wander around by yourself, can you?”
“Everton… you’re such a—”
“Father’s covering Freya’s costs. But your 150 million credit share… pay it back to the treasury. Mwah~”
“Even royals have to pay off national debt!?”
“If there’s a gold coin on the ground, would you pick it up?”
“Of course.”
“And if a beggar picked it up, would the coin lose its value?”
“No.”
“Exactly! Doesn’t matter who picks it up. What matters is 300 million credits just left the treasury today.”
“What the hell does that have to do with anything!?”
“You have to pay it back, prince or not. Now, sign here. Sign this life long contract.”
“One hundred and fifty million credits…”
After signing the contract and taking on the massive debt, Fury and Freya began the transformation ritual.
They could only choose once. The human form they picked would be theirs forever.
No do-overs.
Everton pulled a sheet off a row of glass cases, revealing preserved human bodies collected from past wars.
“Think of them as reference templates. Male and female.”
Ahem.
“There are various body types—fat, stocky, average, skinny. Skin tones in multiple shades. You name it. As for appearance, cabinets three and five are rumored to have the best-looking faces.”
Freya’s jellyfish tendrils shot straight toward cabinets three and five. Fury just rubbed his chin, thinking.
“This one, this one, this one, and this one!”
Freya smacked the glass with her tendrils.
She chose a female body that matched the human form already described. The original had black hair and less curvy proportions, but those could be modified later.
“I want this one! I’ll be the most dazzling human in the whole kingdom!”
“Keep it modest. You don’t want to stand out too much.”
“Oh come on! We only get to choose once! Of course I’m going full-option female human!”
“If you were a hunter, would you chase an ugly rabbit or a beautiful one?”
“And if you were a butterfly, would you live in a garden or a graveyard?”
“I’m trying to give you sincere advice! Why are you always twisting it!?”
“I’m one of the hottest Diablos around, and I’ll be the hottest human too. Your Highness, you don’t get to boss me on this.”
“Isn’t defying a crown prince against the rules?”
“Do knives hurt, Your Highness?”
“Yes.”
“Well, not being beautiful hurts more. End of discussion.”
“What the…?”
Fury sighed, gave up, and pointed at a random cabinet.
It contained the body of a young male soldier around 16–17. Completely average. Plain face. Average build. Nothing stood out.
“I’ll take this one.”
“Want to customize it?”
“Whatever. It’s not like I plan to live in this form forever. Actually… make the personality a bit more appealing.”
“Got it.”
And so the ritual began.
Two thousand tons of mana crystal—worth 300 million credits, equal to the GDP of the five kingdoms for two years—were sacrificed.
Crown Prince Fury and his bodyguard Freya were now owners of human forms.
“Why are you so tall…”
The black-haired boy looked up at the towering woman. He was 170 cm. She was 180.
“She’s the same height as Casca… So this is how humans see her…”
“You look like a bunny, teehee~”
“Five hundred thousand years.”
“Alright, listen up!”
Everton opened a grimoire containing the transformation rules.
“This is important. You’ve probably read it already, but I’m going over it again.”
The spellbook from the Shadow Kingdom, confirmed by previous Diablo spies, stated:
You will lose all of your original strength. You’ll have the physical ability of a regular human.
Anything that happens to the human body stays with the human body. Same applies to the Diablo form.
Mana control will improve—but how much depends on the original body’s potential.
“Looks like Freya has the edge here. Her template is an assassin from the Kingdom of Velmouth.”
“So I have better magical potential in this body than Prince Fury?”
“Yep. His body is… uh…”
Everton glanced up.
“Just some dumb soldier…”
“Dumb? I’m that dumb?”
“Okay, maybe not that dumb. It’s stronger than average, sure—but he died young, so his full potential never emerged. You’ll have to take it from here.”
“Then I have a question… what’s with the tattoos?”
He pointed at Freya’s right chest, marked with a jellyfish.
“Not just Freya, you have one too.”
“Huh? Where?”
Fury had a tattoo of a six-horned demon on the back of his hand.
“What!? How!?”
“It’s your personal mark. We all have one.”
All Diablos with human forms had a tattoo somewhere on their body representing their true self.
Fury’s demon form had a six-horned skull. Freya’s was a jellyfish-like creature.
—Every Diablo must define their own condition for reverting to their original form.
“We have to set a condition?”
“Exactly. The grimoire says you must choose a method for transforming back and forth. It’s like setting a password.”
“We can pick anything?”
“Anything. Just choose wisely.”
“Got it…”
The prince and his bodyguard leaned on their hands, thinking, facing each other.
Flashback—
Before they left the Diablo Kingdom, the Demon King summoned Fury for a private talk.
“You’re strong, that’s true. But in the outside world, anything could happen. I’m not just talking about danger to you, but the unexpected in general. Things that don’t affect you directly but might require emergency help… We need to be prepared. Understand?”
“I do, Father. You’re right. Especially if some damn Shadows are still hiding out there.”
“Then take this.”
“Wait… this is…”
Three green crystals.
“These are signal beacons…”
Fury knew them well. He’d used one in war before.
“Exactly. Crush it and speak your emergency. We’ll know where you are—and send help.”
“I know. I’ve used it once in battle.”
Three uses. Use them wisely.
“I promise to use them carefully, Father.”
“Your mother’s probably given you the list of our spies in human cities?”
“I’ve received it, yes.”
“Good. If anything happens, seek them out—but discreetly. Don’t take risks where you don’t have to.”
“Of course, Father. This is personal. I won’t call on them unless urgent matters.”
The emperor patted his son’s shoulder.
“Take care of Freya… I was going to send Dominik instead but—”
“Please don’t, Father. Dominik’s too valuable for this kind of silly quest. A silly quest should have a silly partner. Freya’s perfect.”