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Part 1 of Friend of Humanity
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2023-07-08
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2026-02-20
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20/?
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Friend of Humanity

Summary:

A boy with black hair and sea-green eyes appears at Kaer Morhen. He's never heard of Witchers and has no idea who the Warlord is.

Well. This might as well happen.

OR

The post-Heroes of Olympus Percy Jackson x AWAU crossover no one asked for that I wanted to write anyway.

Notes:

I have no idea what this is. Have fun!

(See the end of the work for more notes and other works inspired by this one.)

Chapter 1: I Crash a Warlord’s Dinner Party

Notes:

(See the end of the chapter for notes.)

Chapter Text

The boy appears from nowhere, materializing above the center of the main hall and tumbling to the ground, landing miraculously on his feet. He looks surprised at his own prowess, then immediately ruins it by wobbling slightly. He sighs, swears under his breath in a language Eskel doesn’t recognize, and straightens.

He was clearly just fighting: he’s wearing a chestplate, and there’s a bronze sword in his right hand. His breathing is steady but fast, and his face glitters with some kind of gold dust. But his sea-green eyes (and Eskel’s never seen that shade before, even on elves) are bright and clear, though they cloud in confusion when he registers his surroundings. His brow furrows, and his scent spikes with anger.

He doesn’t get time to do much more than that. The Witchers see an angry, clearly-magical stranger with a sword in the middle of their keep, where all their loved ones are, and register him as a threat. A few move toward the human servants, ushering them carefully out of the room, but most go pouring towards the stranger, pulling out weapons as they go.

First to reach him is a Cat, agile and quick, moving faster than a human can comprehend. But the kid (because he is a kid, no older than twenty, and why was he fighting, does Geralt really need to go conquer another country?) somehow manages to duck under the blow, and his own sword comes up to meet the next one, this time from a Bear.

But there are too many of them, and they’re too good. Maybe ten seconds later, his sword goes clattering out of his hand, and Gerring of the Vipers steps on it to prevent him from getting it back. About two dozen Witchers point sharp things at various parts of his body.

He still looks unwilling to surrender. His eyes dart from face to face, searching for a weakness he can exploit, even as his hand drops to his pocket. When he doesn’t find what he’s looking for, he seems about ready to lunge forward anyway, weapon or no weapon. Then Geralt finally stands and says, “Enough.”

The word cuts through the hall, and all the Witchers take a single step back. None of them lower their weapons.

The kid turns to face the main table, brushing a lock of inky black hair out of his face. “Hi,” he says simply. Then, “Think we got off on the wrong foot. I’m Percy Jackson.”

He sounds like he expects the name to mean something, and his scent turns surprised when he sees it doesn’t. Which… doesn’t make much sense, because if he’s still using his family name, it means he hasn’t done anything to earn an epithet. Why would they have heard of him?

“Well, Percy Jackson,” Yennefer drawls, but Eskel doesn’t miss the hand she keeps on Ciri’s forearm, ready to portal them out if necessary. “How did you get here?”

Percy shifts on his feet and scratches his head, looking so awkward Eskel can’t quite believe he’s the same hardened warrior who refused to surrender even disarmed and surrounded by angry Witchers. “That’s a great question,” he replies. “Mind telling me where ‘here’ is?”

A moment of silence. “You don’t… know?” Eskel asks. He portalled in here, he must know, but…

“Wouldn’t be asking if I did,” Percy replies, and Eskel is about to respond when Jaskier interrupts.

“Please answer the question, good sir,” he says with a charming smile. Eskel can see the lines of tension in his body, but he still smells mostly relaxed. And a little turned on, but that’s normal for him, and the fact that he feels safe enough to smell turned on is soothing.

“No, I really don’t know where I am.” Percy’s… not lying. In fact, he doesn’t even smell afraid: his scent is easing away from the sharp taint of anger and moving more towards confusion. He glances around. “A castle of some kind?”

“A keep,” Eskel says. “Kaer Morhen.”

Percy tilts his head to the side. “That doesn’t help.”

“…Home of the Witchers? Seat of the Warlord?” Eskel tries.

“Dude, I don’t even know what Witchers are. Are they just normal witches but more… witchier?” He’s still not lying, and what the fuck is going on. What kind of person doesn’t know what Witchers are? And how does that kind of person get into Kaer Morhen? And Percy is still talking, apparently unaware of how crazy he sounds. “Who’s the Warlord? That doesn’t sound like a nice title. Is he a colonizer?”

What the fuck.

“This is the White Wolf, Warlord of the North,” Eskel manages, because he doesn’t know what else to say. He jerks a head towards Geralt.

“I’m gonna assume you’re talking about the guy with white hair, because if you’re not, that’s gonna be really funny.” Oh, right, Jaskier and Geralt sit together now. “So is that… a title? A name? Like, is your first name White and your last name Wolf? That sucks, man.” Then Percy seems to check himself. “I mean. Did you want me to bow? Because I’m not going to bow. Sorry, I’m bad with authority.”

That’s… new, and Eskel can’t decide if it’s good or bad. On the one hand, Geralt will appreciate not having to convince someone to stop groveling. On the other hand, who is this kid to have that attitude? Where did he come from?

“Still haven’t explained―” Yennefer begins when Gerring interrupts. He’s the one who stepped on Percy’s sword, Eskel remembers, then realizes there’s no blade to be found under his feet.

“Hey!” he growls. “The sword just disappeared. Where is it, kid?”

Percy stiffens, and his scent goes slightly sour. “Don’t call me kid,” he warns. “And uh, I have no idea where my sword went.”

This time, every Witcher in the hall growls, and Gerring springs forward to stand in front of Percy. “Liar,” he snarls in Percy’s face, but Percy lifts his chin stubbornly.

“As I’m sure you’ve noticed,” Jaskier says casually, though he’s gripping Geralt’s arm, “Witchers can smell when you lie. And they don’t like it.”

“Oh, you’re Witchers?” Percy blurts out, which is… not what Eskel expects him to say. “Sorry, you really don’t look like witches. Not enough pointy hats.” He squints at Gerring, taking advantage of the fact that the Viper is a foot in front of his face, then looks around. “The yellow eyes feel on-brand, though. Don’t know why, but they do.”

Gerring snarls again, seemingly deciding to ignore everything Percy says. Eskel would do the same in his place, because there is something deeply wrong with Percy if he’s acting this way, and they do not have enough time to unpack it. “Where’s your sword?” he demands again, and for a moment, Percy stills.

Eskel sees a hint of that hardened warrior again in the calculation that steals across Percy’s face, there and gone, as he weighs his options. Gerring sees it too and moves in a flash, seizing Percy’s shoulder with one hand and taking advantage of his raised chin to press a dagger to his neck― probably poisoned, since he’s a Viper. To his credit, Percy doesn’t look intimidated; in fact, his scent goes faintly amused.

Really, truly, what the fuck is wrong with this kid.

“My sword’s in my pocket, if you really need to know,” Percy says with seemingly no consideration for the knife at his throat. Eskel notices Gerring actually has to move the knife back a little so he doesn’t accidentally nick the kid. (If a Viper’s going to cut someone, it’ll be on purpose.)

And that’s all a distraction from Percy’s words. “What do you mean your sword’s in your pocket?” Gerring hisses. Someone else comes forward ― Joёl of the Cats ― and roughly pats around the boy’s hips.

“Hey, not cool to grope a minor,” Percy mutters, and Eskel can see that he’s gone tense. But he doesn’t try to fight, even when Joёl shoves a hand in a slit on the side and withdraws… a skinny, clear cylinder? About two-thirds of it has a black line in the center, and at the bottom of the line is a black thing with a narrow spar that extends slightly over the cylinder.

Joёl looks up at the main table. “Only thing in his pocket, Wolf,” he says. But they could all smell that Percy wasn’t lying about his sword, and the way he’s keeping his eyes on the cylinder in Joёl’s hands shows that it means something to him. What is going on?

“Bring it up here,” Yennefer orders, and Joёl comes up and gives her the cylinder. She eyes it for a moment, then presses her index finger to it and closes her eyes. The cylinder glows slightly as she casts an examination spell.

Her brow furrows.

The hall is silent.

“I can tell it’s magic,” Yennefer admits after a minute, dismissing the spell with a flick of her hand. “But I can’t figure out anything more than that.” Eskel sees unhappiness on her face, though only someone close to her would recognize it. “Istredd might know more, but I doubt it.”

“You could just… ask me, you know?” Percy offers.

“You’d fucking lie,” Lambert snorts, but Percy shrugs, and Gerring has to hastily adjust the knife again.

“I mean, normally, yeah, but clearly that doesn’t work on you so there’s no point in me trying.” He nods to the cylinder. “That’s my sword.”

“How does it work?” Yennefer asks. Percy shakes his head.

“Magic? I dunno. It got shoved in my hands about two minutes before I went on a quest to prove I deserved to live, so I had more important things to worry about.”

“What.” The word slips out of Eskel’s mouth, and Percy’s scent goes faintly amused. He’s enjoying this, Eskel realizes, which only reinforces his firm belief that there is something very wrong with the kid.

Yennefer, like Gerring, decides to ignore the kid’s words. (Eskel feels like that’s going to become a theme if he stays.) She turns to Geralt. “Vilgefortz ― he’s a Ban Ard mage ― can summon his sword back to its sheath if he loses it. Percy can probably do something similar.”

“Aiden,” Geralt rumbles, and the Cat nods before running out of the hall. A few minutes later, he comes back with a dimeritium chain dangling from his fingers, and Gerring removes his knife from Percy’s neck so Aiden can fasten the chain around it. Percy balks.

“Uh, would really prefer not to have that on if I get a choice?”

"You don’t,” Geralt growls.

“Okay, but it’s not going to, like, mind-control me or anything, right?”

“No, it won’t,” Aiden promises, and Percy eyes him skeptically before sighing.

“Fine.” Once Aiden finishes, Percy tilts his head from side to side to get accustomed to the new weight around his neck. “Was that supposed to do anything?”

Eskel watches him closely. The boy’s not turning green, or rubbing his head, or showing any sign of discomfort at the presence of dimeritium. At that moment, Yennefer makes a noise. The cylinder in her hand is gone.

Percy reaches slowly into his pocket and draws out the cylinder. He holds it loosely and makes no move to attack anyone, but the Witchers around him tense anyway.

“Yeah, uh, I don’t think the chain did anything,” he says.

“What the fuck,” Lambert says flatly. Eskel’s inclined to echo the sentiment.

That… should not be possible. Only extraordinarily powerful mages can overcome the presence of dimeritium, and if Percy’s really that powerful, what’s he doing using his magic to summon swords? An earthquake or a hurricane would be much more effective if he wants to escape.

Or maybe he hasn’t been trained, and summoning swords is all he knows how to do? But then how’d he get such advanced magic on his sword that Yennefer can’t recognize it? Just who the hell is this kid?

But more pressingly, Eskel reminds himself, directing his attention back to the now, how do they get the sword away from him?

“Can I just… promise not to attack you and we can move on?” Percy offers. “Like, not to blame anyone, but you guys were totally the ones who jumped me. I was just defending myself.”

Geralt thinks for a moment, his face stony, then nods. “Give your oath.”

“I swear on the River Styx that I won’t attack anyone unless I’m attacked first.” Thunder booms, sounding like it’s coming from inside the hall, and everyone jumps.

“What the fuck was that?” Lambert demands.

“Um, it’s a magically-binding oath where I come from. If I break it I die and then my soul gets tortured for eternity, so… I’m gonna try not to break it.” He grins brightly and sticks his thumbs in the air.

He’s not lying. In fact, he hasn’t lied since that thing about his sword. Geralt nods, accepting his oath, and the Witchers around Percy relax. Most sheathe their weapons, though no one moves to resume dinner.

“Where do you come from?” Yennefer asks.

“New York City. Maybe you’ve heard of it? It’s in New York.”

“No, actually,” Eskel says slowly. “I haven’t.”

Percy’s scent spikes with shock that’s visible on his face. “New York City? In America? The good ol’ US of A?” Eskel shakes his head. “Well. That’s awkward. Uhhhh. Considering I’ve never heard of Witchers or Warlords before… what are the chances I got dropped into a different world?”

Yennefer blinks. “We know dimension travel is possible,” she says, and carefully doesn’t glance at Ciri. “Don’t ask,” she adds at the look on Percy’s face. “That does seem like the most likely option.”

Percy sighs, and his scent mellows into resignment. Though he seems surprised, he doesn’t seem nearly surprised enough for the situation. Even Eskel is having some trouble wrapping his head around the idea, and he’s not the one who’s just dimension-hopped.

“What were you doing before you got here?” Yennefer asks.

“I was fighting some hellhounds, big black dogs with glowing red eyes―”

“We have hellhounds here too,” Eskel interrupts, “though the description sounds a bit different. Are you some sort of monster hunter?” Because of course their dimension hopper does the exact same thing as a Witcher. Destiny just loves playing with them.

Percy blinks. “I guess? I mean, technically, they’re usually the ones who hunt me, and then I have to kill them.”

“Why do they hunt you?” Vesemir asks.

“Because apparently I smell really good.” Seeing the confusion on their faces, Percy elaborates. “Where I come from, there’s a group of people called…” He hesitates. “…half-bloods. And monsters really like the way we smell? Which sounds weird now that I’m saying it out loud. Anyway, they track us down using our scent and then try to kill us, unless we kill them first.” Percy grimaces. “It’s not fun.”

The hall is silent for a moment. Then Gerring sticks his nose into the juncture of Percy’s neck and shoulder and inhales deeply.

“Hey, man! Not cool!” Percy yelps, jumping backward. Gerring stays where he is and looks thoughtful for a moment, then shakes his head to clear it.

“Smells like the ocean,” he says, turning to Geralt. “Salt and a sea breeze. But…” His brow furrows. “There’s something underneath I can’t describe. Not strong, but really distinct. Now that I know what it smells like, I think I could track the kid anywhere in the keep.”

“Not a kid,” Percy says again. “Would there be any way to hide it?”

“Triss might know.” Gerring nods to the sorceress, who waves. “But I’m not sure. I’ve never smelled anything like this.”

Percy is almost vibrating with excitement. “Can you talk to me more about it? If we know how the scent works we might be able to find something that blocks it. And you said it’s not strong; do you think that might be related to my age? I’m one of the oldest, and―”

“One of the oldest?” Geralt growls. The entire hall goes still, and Percy’s smile falls.

“Yeah. Monsters start hunting us at twelve and… most of us don’t live to our twenties. I’m seventeen, and.” Percy shrugs. “That’s already a miracle. I never expected to get this far.”

His scent is melancholy, but he’s telling the truth.

“That’s why you kill monsters,” Eskel says softly. “You don’t have a choice.”

“Yeah. We learn to defend ourselves, or die.”

The sentence lands heavily in the hall. Though things have improved since Geralt became Warlord, every Witcher remembers the feeling of being forced into the violent lives they lead now. And even back then, they were the ones seeking out monsters, preparing for the fight, and deciding the battlefield, not waiting for an ambush every second. It sounds like a miserable way to live.

“Witchers hunt monsters too,” Eskel offers, a truth for a truth. “We used to wander the Continent, risking our lives to take contracts and earn enough money to survive. Geralt was the one who realized that some humans were monsters too, and therefore fair game.” He shrugs. “So here we are.”

Percy eyes the hall around them. “Feels like you skipped a few steps there, but okay.” His levity is slightly forced, but he’s about to continue speaking when he’s interrupted by his stomach grumbling. “Sorry,” he says sheepishly. “Like I said, I was just fighting. If you’re not gonna kill me, can I get some food?”

Notes:

YES THAT WAS A GLEE REFERENCE. I have not watched Glee but I know that line, just because.

This popped into my head and refused to leave. I don't know where it's going or what Percy's doing there, but we'll figure it out as we go!

There are SO MANY parallels between demigods/Witchers and I have Ideas. If I ever get around to them. Like, Witchers are the bridge between mortal and monster, and demigods are the bridge between mortal and god, but who's to say that gods aren't monsters?

Working title for this was The White Wolf and the Blue Pancakes because I couldn't think of anything else to represent Percy. I made the executive decision that that was NOT going to be the official title. Also somehow socks got in there, and I'm blaming my friend for that.

Fun fact I have THREE different introductions for the very beginning of this fic. Version 1 was Percy just gets dropped in while he's having lunch with Annabeth or something, and he's really chill. Then I decided I wanted him to be more BAMF, so I rewrote it where he's in the middle of a fight. THEN I decided I still wanted him to have the Curse of Achilles (because we're hand-waveying canon and I wanted to write the Witchers reacting to it) so I rewrote it AGAIN. It was very fun.

Thanks to the AWAU Discord for getting me hooked onto this crossover! Actually I don't know if I should thank them or curse them, because I foresee that this will Consume My Life, but it's a little too late for me to do anything about it. The only way out is forward!