This pale kid is Percy's cousin? And where did he came from?

"Percy, Annabeth is going to kill you! You've been missing for three days until your mom called and tell us you escaped. Both camps are worried." Nico the kid reported.

Percy cringed. "I'm sorry, man. It was unexpected. I wonder if Blackjack is worried by now. Anyway, how did you find me?"

Nico rolled his eyes. "You know that I can do it, right?"

"Yeah, my bad. Does Lady Lupa aware of Lycaon's activities here in California? I'm sure they know about it. Have you asked Reyna?"

"They can handle themselves," Nico said. "The problem here is you. You went missing again and I find you here with two unknown guys."

Dean looked offended. "Look here, kid. Your cousin wants to avenge his abduction together with my little brother, so he's here."

Nico raised an eyebrow. "Really? When did you like to hunt? As far as I know, that's Thals specialty."

"Hey, just wanna try it. Besides, it might be fun, you know?"

Nico sighed. "By the gods, what should I do to you? If you die there, I'll drag your soul from Elysium to fields of punishment."

Their conversation is getting weirder by the words they utter. Elysium and fields of punishment? It doesn't sink in Sam's head.

"Don't worry, I won't. Thanatos gave me a pass to escape death." Percy grinned as he wiggle his eyebrows. "Just tell her to try to hunt them."

"Whatever." Nico rolled his eyes. He's not entirely out of the shadows, but he's wearing dark clothes for my liking and a stick is hanging in his left side.

A stick? How can he defend himself with a stick?

"Shouldn't you be at infirmary? Your boyfriend will get angry if he found out you're missing." Percy said.

The kid blushed. Wait, did Percy say boyfriend? The brothers thought.

"This is an emergency. The camp's leader is missing. Everyone is on edge. That might be a plot of the Queen."

"Oh, I swear to you. Queen cow won't do that again unless she wants a war."

"Wait up. What the hell you kids are talking about? You talk like we don't exist." Dean interrupted.

"This is a family matter, Dean," Percy said.

"Does that include with mutts?" Sam asked.

"Yeah. Every tragic happens to us, blame the Olympian parent for that." Nico said.

A clap of thunder rolled over the sky like someone was watching over them and giving warning.

"What?" Sam and Dean chorused.

"Nevermind," Percy said. "So, when we'll start hunting them?"

Percy sound was so ecstatic that Nico can't do anything, the latter sighed. "I'll just tell Thals then, good luck. See you at camp, cuz."

Nico turned back to the dark part of the room and disappeared. Dean opened all the lights and didn't found Nico.

"Where the hell is your cousin?" Dean wondered.

"Gone. He's going back to camp and try to call our cousin." Percy said.

How come the kid goes in and out of the room without using the doors? Unless the kid is a demon or an angel like Crowley and Castiel. Sam thought.