Five Times Percy Didn't Adult and the One Time He Did

Six: Nico

Near the end of every summer, Camp Half-Blood hosted a swordfighting tournament; Percy had been banned from competing and instead was the co-arbitrer with Annabeth. They had to give the other kids a fighting chance for the laurels and title.

It was a huge affair. The Hermes cabin and the Demeter cabin combined resources to create a banquet that even Olympus would be jealous of, and even ordered European food baskets months in advance. 

And every summer, Will Solace spent a sleepness night drilling his siblings and preparing the infirmary for the slew of patients that would be coming in. Austin triaged them as they arrived, Kayla took the minor cases- a graze or a broken jaw- and Will spent his day in the back, making sure no one died from the tournament.

The Apollo Cabin had tried petitioning for it to end, but there had been no luck.

Mr. D had been adamant that it continue.

It was the first year Nico was competing- he'd never been around or interested enough before, but he was an excellent swordsman and with some encouragement from Hazel (and some coercion from Thalia), he found himself in the arena, ready to face his first opponent.

He dispatched him quickly; a step in, a parry to the side, flats of the blade, point to the chest. An Ares girl was next, and she was harder to win against. She grazed his cheek, Nico sidestepped and tripped her. She kneed him as she came down, he twisted to evade a sword and disarm her. He made it through his first round.

Hazel and Thalia cheered him on the loudest. Percy, who by virtue of being an arbitror, was required to remain impartial at all times, snuck him a wink. They'd spent hours training together during Percy's time off from university.

He cleared the arena, letting the next round begin, and propped his sword against a tree before grabbing a cup of water. Thalia was already waiting for him at the food tables, with two plates in her hands: one for her, one for him.

"That's my little cuz," she grinned, handing him a plate and then ruffling his hair.

"I'm older than you. Technically."

"I'm immortal."

"Did I do okay?"

"You did great," Thalia smirked. "Annabeth looked a little too smug. I don't think she's as impartial as she's pretending to be."

"Percy winked at me," Nico smiled back at her. It was hard not to be excited with Thalia. Her energy quite literally was infectious. He hadn't been able to prove it, but Nico was certain it was something the Zeus kids could do: transfer electrons at will and share their energy.

He started nibbling at the food as Thalia kept talking, sometimes throwing in his own thoughts. There was some time before his next round, and they watched from the side of the arena as they ate.

Percy was out of his seat almost before the commotion began- so fast that Thalia barely had time to shout before he was there.
His mind was working overtime the second he started moving. 
This was all too similar.

"I don't-" Thalia began, but Percy wasn't listening. He had his Epipens with him (he always carried them now; he didn't fancy another letter from Hades complaining about how Poseidon would react) and even if he didn't know what Nico's allergy was, he knew it was a reaction.
It was all the symptoms he always had.

Percy Jackson did not hesitate.

"You didn't know you had an allergy?" Will whispered yelled, hours later, once Nico was feeling better and Percy had calmed both of them down.

Nico shrugged; he certainly didn't have any medical records and he didn't remember anything from before the Lotus Casino. How was he supposed to know?

Will huffed, adjusting his lab coat, and sat down on the bed next to Nico. "I gotta test you later. That was definitely a reaction and you are definitely allergic to something you ate."

"I lost the contest."

"Nah, Percy put it on hold. He said they'd finish it when you were back."

"I can go now-"

"Day in the infirmary. Doctor's orders. And I gotta test you."

Nico started pouting, but Will curled up next to him and started playing with his hair before he had a chance to.

"I gave him the food-"

"Still not your fault, Thalia," Percy repeated himself. Again. He'd lost count of how many times he'd told her.

The contest had already been cleaned up- after Percy's announcements, everything had disbanded in the blink of an eye. No one wanted to continue without Nico. The two cousins were walking along the deserted arena as they talked, giving Nico some time with Will before they smothered him, too. 

"Nico will be fine. He'll get Epipens and he'll learn to live with it. I'll help him. I've gotten pretty good at it."

"I fed him-"

"You didn't know. Now, we do. We'll be careful."

"You're not careful, though," Thalia side-eyed him. She knew it wasn't her fault, but Nico was her little cousin. It was hard to see reason. "Actually, Jason told me once about-"

"My point is, Nico will be fine," Percy said quickly. "Maybe him and I can be the allergy duo."