This Treaty of Inviolable Friendship

A/N: Grabi-hand's fanfiction repost

Not everyone got to spend Valentine's Day riding a triceratops, but then, not everyone had a son of Hades for a boyfriend.

Of course, Percy would be pretty pissed if they did - he was almost certain that Nico was the only one.

•

They'd been wandering through the Fields of Asphodel on the back of Mrs. O'Leary for the past half an hour, and Percy was starting to seriously hate gray. Whatever Nico was looking for, he hadn't found it, and 'Are we there yet?' seemed like sort of an insensitive thing to say. Especially on Valentine's Day.

Percy said it anyway.

"No," Nico growled, but a second later he grinned like he couldn't help himself, and that was one of the thousand and one things that Percy loved about him - well, the grin made it a thousand and two. He knew when it was worth getting angry. He didn't take himself too seriously. "It's around here somewhere, I'm sure of it."

"Didn't you say that the last - uh - " Percy looked around him, but there really didn't seem to be anything different from this giant plain of gray souls and the last one, or was there even really a difference? "...field? How can you tell them apart, anyway?"

Nico made an impatient sound, which obviously meant that Percy was an idiot if he couldn't see what Nico saw, and the son of Hades refused to speak with idiots. It was awfully pretentious and kind of ridiculously endearing.

It would have been a rather nice moment if Percy was capable of keeping his mouth shut. "You know, if this is your idea of a romantic getaway-"

"Oh, shut it," Nico snapped, without any bite behind it at all. "You'll find out soon enough."

"When? When the dinosaurs come back to-"

"There! Can you see it?" Nico leaned forward and pointed off into the distance, where Percy had a very lovely view of absolutely nothing.

"Yep. Totally. Absolutely. I can see the shit out of that unchanging grayness." He did, however, have a great vantage point to ogle the curve of Nico's back, where his tight black shirt had ridden up a few inches. "Mm."

Nico rolled his eyes and scoffed over his shoulder, which just made his spine twist in an all-too-appealing way. "You have the magical sight of a brick. Hup hup!"

They took off toward the horizon at a dead run, flattening souls in the process and making Percy cling to Nico's waist for dear life. He'd take riding a pegasus any day, thank you, no matter what certain people named Annabeth said about crotch bruises.

On the other hand, he got to cling to Nico's back, but he much preferred doing that when they weren't flying along at warp speed.

He could see it now - a glow, in the distance, almost like sunlight peeking through layers and layers of clouds - but that was impossible, wasn't it? They were past the gates of Tartarus, the sunlight in Elysium had been left far, far behind.

Besides, this light looked... different.

The ghosts around them blurred, and lengthened, and it almost felt like they'd taken on a life of their own, swirling in shapes that should have been impossible at this speed. The glow grew brighter and brighter. For a split second, it was like shadow travel - the impossible rush, the enormous amount of energy, even though the gray gave way to white instead of black - and then, just as suddenly, they were at a standstill.

If Percy's jaw was physically capable of hitting the ground, it would have.

They were in a jungle. A jungle like nothing Percy had ever seen, or even imagined - even the smallest of the plants were almost as big as Mrs. O'Leary, the trees soared higher than skyscrapers and the very air itself was thick and heavy with humidity and timelessness.

"...So you're telling me, that somewhere in the Fields of Asphodel, there's a secret pocket universe full of dinosaurs."

Oh. Yes. There were also dinosaurs. Lots and lots and lots of dinosaurs.

Nico smirked, utterly full of himself. "Yes."

"And you brought me here, for Valentine's Day."

"That was the plan, yes."

Percy couldn't stop staring. Something taller than his shoulder with an enormous frill all down its back was winding through the tree trunks, and overhead, a flock of birds twice the size of bald eagles chased each other, the bright colors of their plumage catching the sun. "I think I love you."

"Not yet you don't." Nico leaned close to whisper in Percy's ear. "Just wait til you ride one."

•

And that's how it came to this - wandering through the late Cretaceous period, perching in the crook of a triceratops's horn, one hand gripped tight to the edge of its neck frill. Percy could not contain himself. The skin under him felt pebbled and leathery and cool, and the triceratops - who Percy had affectionately named 'Pokey' - seemed completely unconcerned about having a passenger.

Several dino-lengths away (Percy was going to use that term forever), Nico was sitting crosslegged on the back of an ankylosaurus - though, Percy thought the name should officially be changed to 'badassasaurus'. Its entire back was plated in thick pebbly scales, harder than rocks, and a line of enormous spikes marched around its sides like the edging of a shield. Try riding one of those into battle, he thought, and it made him smile from ear to ear. He could see it so clearly - Nico in his bloodwashed black armor, a red cloak billowing out behind him, sword in hand, terrifying and beautiful.

"Penny for your thoughts," Nico called out, and the smirk was back, like he'd just caught Percy staring. Which, well, he sort of had.

He grinned and leaned his head back against Pokey's frill. "Just thinking how great it would be to ride these into battle."

"I think about that all the time," Nico said with a laugh. "Can you imagine? The monsters wouldn't know what hit them."

That provoked the mental image of the Minotaur going head-to-head with Pokey, and Percy couldn't help the giggles bubbling up out of his throat. "Right? Bronto versus the titans! Try that on for size, Oceanus."

Nico started giggling, too, though he tried to clap a hand over his mouth. "Kronos would've run away screaming!"

They couldn't stop laughing for a long minute and a half, until finally Nico slumped over backwards and lay spreadeagled over the ankylosaur's back. Percy stared up at the sky, completely entranced. It looked like blue that had been washed in gold - so faded that nothing but the memory remained. As he watched, a shadow passed over the sun - the unmistakable silhouette of a pterodactyl.

He felt his heart wrench at the sheer magnificent beauty of it all. "How does this even..."

"...exist?" Nico's voice sounded as faraway and entranced as Percy felt. "This is the First Afterlife, Percy. It's the foundation on which the entire Underworld is built."

"It's like... dinosaur heaven?"

"Mmhm."

They lay there for a long time, watching the trees and birds scroll by, as their dinosaurs lumbered on. "Nico?"

"Hmm?"

"Can I love you yet?"

"Nope." Nico gave him a sly, deliberate smile, that never failed to set his heart pounding a little faster. Then he rolled forward and smacked the ankylosaur on the shoulder, which it absolutely did not feel. "Come on, Spikey! Just a little farther."

•

'Just a little farther' turned out to be the beach.

Pokey went right up for the water, presumably to wash off his talkative parasite - and Percy slid off into the shallows, absolutely boneless with shock.

Groups of waist-high raptors chased each other across the wet sand, their claws leaving long gashes behind them in curving patterns. A pair of hadrosaurs fussed with a brood of children, dunking them in the water and persistently ignoring their little screeches. Further out, a titanosaur - and, when Percy remembered why it was called that, he almost laughed, because really, this was much more impressive than a titan - lay basking in the sun. Its long neck was stretched limply out over the surface of the water, bobbing about like a cooked noodle.

Nico sloshed up behind him and wrapped his arms around Percy's wist, letting his head rest against his back. The age difference still accounted for the foot of separation between their heights, but Percy had no doubt that Nico would catch up to him soon enough. Italians were supposed to be tall, right? But for now, he was at the perfect height to kiss that spot between his shoulder blades, and Percy shuddered.

"All right, you can love me now," Nico murmured, with a smile that he could feel rather than see.

Percy considered saying something snide in return, but he was just plain too happy. The sun was warm, the water was tepid and heavy and ancient, and he'd just ridden a dinosaur. He snaked one hand back and hooked it on Nico's belt - a thick black monstrosity hung with enormous silver skulls, which made him all too easy to grab hold of. "I actually don't think it's possible for me to thank you enough," he finally managed.

"Might be fun to hear you try," came the impish reply, with a smirk pressed to Percy's shirt. He laughed.

"You'd get bored."

"That depends," Nico purred, and his fingers were inching under Percy's shirt now, to tease at sweat-slick skin, "if I was allowed to distract you or not."

"Definitely not," Percy countered, though he was slowly melting back against him and that wasn't really helping his case, was it? "That just wouldn't be fair."

"Mmm," Nico said, and then he was kissing his back again, and Percy let out a strangled whimper that was entirely unmanly, but who would care? The dinosaurs?

He pulled away and they raced deeper into the water, until Percy caught Nico up against the side of the titanosaur, and his laugh bounced and danced like an anemone. He kissed him until he couldn't breathe, licked at his neck until he could, and kissed the breath out of him again. Nico's hands scrabbled at his sides, trying to reach his weak point, but his skin was too slippery, and he finally gave up and clung to his hips with a death grip.

The water was... heady, like a fine wine, and Percy had drunk from the wine of the gods, so he would know. His tongue slowed and he savored it, crawling with life and otherness, and Nico gasped sharply when he bit down, chasing the taste down the corded muscle at the base of his neck.

When he pulled back, gasping for air and a semblance of sanity, Nico took the opportunity to flip them around, and suddenly Percy was the one under siege, caught between Nico's pointed tongue and the warm pressure of the titanosaur against his back. Rational thought utterly deserted him, and for a long minute, he was lost to sensation and his own moans.

For a minute, though, he let his eyes roam along the bank, and for a split second, he could've sworn - but no, it couldn't be. That was impossible.

For a second, he'd seen the shape of a beautiful old satyr, dancing through the trees.

•

They stopped at Hades's palace on the way back, because the water refused to leave their clothes, no matter how much Percy pleaded with it.

Nico snickered. "It doesn't want to listen to you," he teased.

"Not funny. We can't go back like this, it's February." Also, as much as he loved water, Percy kind of hated the feeling of being wet, when he wasn't, you know, submerged. He was too good to get wet, damnit.

"Aww. Poor bedraggly Percy." Nico leaned back and nudged Percy's chest with his shoulder, and squeezed the arm he had wrapped around his waist. "We'll stop at my room and get a change of clothes, how's that?"

"...and a towel," Percy ground out, though he was much too happy to be actually frustrated at anything right now. He grinned a sappy grin, and nuzzled the back of Nico's head, and life was wonderful.

They made it as far as the front hall.

"DAD!" Nico screeched, dropping the bundle of wet shirts to clap his hands of his eyes. "What the HELL?"

Percy was, admittedly, still in a bit of a post-orgasmic (and post-dinosauric) haze, but he couldn't help thinking how ironic it was, swearing on Hell when you're, you know, in it...

"Hi, Nico," Hades said in a cordial tone, as if he was discussing the weather.

"Hi," Persephone added, a bit belatedly, and she sounded quite breathless indeed.

"I thought you weren't going to be home all day," Hades continued, though after a moment he placed a hand over his wife's mouth. She was making some embarrassing noises.

"Apparently, I should've been," Nico snarled, pressing his hands deeper against his eye sockets, like maybe if he pressed hard enough he could erase his brain. "Seriously? The FRONT HALL?"

"I like banisters," Persephone supplied, which was not helping Nico's case.

Hades sighed. "And I dislike hypocrites. You stink of sex. Get out of my sight." He turned and smiled over his shoulder at Percy, which was somehow more terrifying than what they'd walked in on - which he was not, repeat, not staring at, because his boyfriend's dad was not remotely attractive. At all.

"Come on, Percy, let's go," Nico muttered, grabbing Percy's hand like a vice and dragging him right back out of the door. "We'll go find somewhere else to be."

•

They ended up at the banks of the Styx, at the very spot where Percy had taken his bath of invulnerability, and Nico had watched, heart pounding, terrified and worried and a little bit in love. Percy knew that now, had seen it a thousand times in the way his lips thinned sometimes, as he stared through Percy's chest to the invisible weakness in his back. He still worried.

Percy wrapped his arms around Nico's chest and pulled him close, back to front, nesting their bodies together like seashells. So much had changed since then.

Suddenly, an arm shot up from the river - a dead, ghostly arm, and with a creaking sound, the rest of the body pulled itself up, until a man was propped on his elbows on the banks of the Styx, gazing almost lovingly at the couple there.

Percy gave him a really, really weird look.

Nico sighed. "Oh no. Come on. Get back in the water."

"But it's so cute. I'm just overwhelmed. You can't possibly expect me to head back for another round of eternal torment when I can watch this, instead, can you?"

He was youngish, in that old-world sort of way where it was hard to tell whether he was thirteen or thirty. The style of his clothes said 'roman', the hair said 'poet', and when Nico squirmed he said, "Catullus."

"And today of all days! It's my absolute favoritest day in the whole wide world, I'll have you know." He smiled coyly at Percy, which might have been charming if it wasn't so not.

"Please go away." Nico's hand tightened on Percy's arm.

"If I could play at kissing your honeyed eyes as often as I wished to..."

"Catullus," Nico snarled, and there was genuine threat in his voice now. "Do not start spouting poetry at me. Or Percy. I will make you regret it."

The poet's smile curved into a sinful bow, and Percy knew that was utterly the wrong thing for him to have said.

"My dear, unless your delights were tasteless and inelegant, you'd want to tell, and couldn't be silent. Surely you're in love with some feverish little whore; you're ashamed to confess it. Now pointlessly silent, you don't seem to be idle of nights, it's proclaimed by your bed garland, fragrant with Syrian perfume, squashed cushions, and pillows here and there and the trembling frame shaken, quivering and wandering about. But being silent does nothing for you. Why? Spread thighs blab it's not so, if not quite what foolishness you commit. How and whatever you've got, good or bad, tell us. I want to name you and your loves to the heavens in charming verse."

"You wrote that for Flavius," Nico said flatly, and Percy had no idea what he was actually talking about, but he thought the poem was beautiful.

"The artist's hell," Catullus said sweetly. "We can't create new material. I really did drop by to wish you well, you know."

"You're doing a fine job of it. Not."

"I've one more for you."

"Leave us."

But it was Percy that Catullus was looking at, who's face he was studying. "Do you want to hear it or not?"

And before Nico could respond (in the negative, most likely), Percy found himself saying "Yes."

The poet's smile was honest, now, and it was charming this time, it was sweet and loving and a little distant.

"You, my life, promise that this love of ours between us shall be agreeable and last forever. Great gods, arrange for him to speak the truth, and to say this sincere and from the bottom of his heart, so that it is granted us to continue all our life this treaty of inviolable friendship."

Percy's arms tightened, and something in his chest did too, curling around the big heart that was supposedly his weakness.

And even though Nico said "You changed the pronouns," his voice was quiet, and thoughtful, and he wouldn't meet the ghost's eyes.

"Good night, lovers," Catullus murmured, and then he was gone, slipped back into the dark waters of the Styx.

Nico pressed the heel of his hand to eyes that had suddenly grown wet. "He just wants me to free him his punishment," he muttered, voice dry and wrenched with emotion.

"Maybe," Percy whispered, passing his hands through Nico's still-damn hair.

"He comes to see me all the time."

"Mm."

"I think I've heard all of his poems by now."

"And?"

Nico twisted until he could look Percy in the eye. "...He wrote a poem where he threatened to sodomize someone. And facefuck them."

Percy snickered.

"What?"

"Sorry. Not funny. ...You said facefuck."

"I swear you're younger than I am," Nico growled, shoving at Percy's shoulder, and resolutely ignored him when Percy just laughed.

"So what, you have something against sodomy?" Percy teased, nosing at the side of Nico's face.

"No, obviously, just - it was a sin in his time, and - "

"Haters to the left."

"Will you shut up?"

Nico shoved him down to the ground and straddled his hips, which wasn't exactly making his point or anything, but Percy wasn't about to complain. He slid his fingers back into Nico's hair, and just smiled when Nico tried to glare at him. "Nico?"

"What."

"Set Catullus free."

His eyes snapped open. "No. I can't - I mean, I could, but - "

"It's Valentine's Day." He leaned up and licked at Nico's lower lip. It was almost as addictive as the dinosaur water had been. "Set Catullus free."

And Nico might've only conceded because he figured, at least they wouldn't get bothered any longer, but Percy knew better. There'd be new poetry, now, and the pronouns would be right the first time around.

•

"Did you have a good Valentine's Day?" Sally asked as the boys popped into the living room, shedding damp clothes and grabbing for warm blankets.

"Nothing went as planned," Nico scathingly informed her, before stomping into Percy's bedroom.

Percy watched him go, then turned to his mom with a brilliant smile. "It was perfect."