Nico couldn't say that he was completely surprised when Serena was claimed by Poseidon. It was surprising from a theoretical standpoint-finding another child of the Big 3 was something nobody in camp could have possibly predicted-but having met her, there was little else she could have been. She looked too much like Percy to rule out the possibility, and her hesitance at cabin 3 spoke louder than words. The other demigod in question, however, had looked like she was going to pass out when Chiron announced who her father was. Eventually, she had passed out and collapsed, but it was from the exhaustion that came with overusing her powers, not from shock.
Of course, Nico and Percy got the job of carrying her to cabin 3, while Annabeth retrieved her small blue rucksack from cabin 11. Nico couldn't complain though; she wasn't really that heavy, and Percy did most of the work. As he was looking at her, he couldn't be surprised at who had claimed Serena. If anybody else had looked her in the eyes, they would have come to the same conclusion. While she was unconscious, her eyes couldn't be seen, but Nico could remember the bright sea-green they had been. When he had first seen them, he had immediately thought of Percy. Now that he was thinking about it, looking at the two half-siblings, Nico couldn't help but notice the small similarities between them. To begin with, they both had messy hair, and while it wasn't very noticeable, their hair seemed to always be at least a little wet. From the small amount of time that he had known her, Nico remembered the little sparkle in her eyes; it had made her seem like her mood could change at any second, but it was also a bit mischievous. When Nico thought about it, Percy had that small sparkle in his eyes too, but it wasn't as bright as Serena's.
The son of Hades smiled inwardly at the pair of half-siblings as Percy put Serena on one of the many empty beds in the cabin. From the way Percy treated her, it was really believable that they were siblings. Percy treated her like a little sister, at least, from Nico's point of view. Nico was shaken from his thoughts when Annabeth walked in.
"Well, can't say I was surprised by this," she stated, setting Serena's rucksack next to her bed.
"What?" Percy asked, confused. "I didn't see this coming." He gestured to his half-sister on the bed.
"Well, If you didn't notice that her eyes match yours, there's also her stubbornness. That matches as well." Annabeth said.
"Hey!" Percy protested. "I'm not that stubborn. I saw her eyes. Besides, I'm smart enough to know not to mess with you."
"You only say that because she's your girlfriend." Nico noted, letting a smirk form on his face.
Percy opened his mouth like he wanted to say something, but paused. After a moment, he decided to speak. "Touche`." Annabeth broke into laughter.
"I'm sorry! It's just the way that you said it," she gave Percy a quick kiss on the cheek before turning to Serena. "Is she going to be okay?"
"Yeah," Nico responded, turning his head towards the unconscious demigod. "She's just tired from overworking her powers." Nico sighed. "I didn't even think that what she did was possible."
"I've never seen anything like it." Annabeth muttered. "Can you do anything like that Percy?"
"Not that I know of," Percy shrugged. "But I guess it makes sense. I mean, my father doesn't have control of only one thing. Nico, you and Hazel represent Hades's two spheres of power, death and riches, but neither of you can control the other's power, right?" Nico nodded. "So my guess is that we each got a different sphere of control, like, mine is water, and her's is earth."
"That's...pretty smart, Percy." Annabeth admitted, receiving a grin from her boyfriend.
Then, Serena groaned and her eyelids fluttered open. She tried to rub the sleep out of her eyes as she sat up.
"Ugh, what happened?" the younger demigod asked after she had found her voice.
"You overused your powers. You'll be fine in a few minutes." Nico explained.
"Did we win?"
"Uh, yeah, we won..." Percy looked to Nico, who nodded. He continued carefully. "And...well...you were claimed."
Serena blinked a few times. Then the confusion in her eyes cleared. "Oh, now I remember. So that really wasn't just a dream? I really was claimed by Poseidon?" Nico nodded. "Wow...I never even thought...wow."
"Yeah," Percy gestured around the cabin. "So now you'll be staying here in cabin 3."
Suddenly, the door opened and someone rushed over to Serena. Nico recognized the someone as Will Solace.
"Hey, Will." Nico said. "Don't you have to be in the infirmary right now?"
"Well, there are other healers than me, and I'm here for Serena right now. Not for your complaints." He directed a smirk to Nico. "I got enough of those when I kept you in the infirmary for 3 days."
"What in Hades did Nico do to get himself stuck in the infirmary for three days?" Serena asked with a teasing look on her face.
"Not important right now." Will said.
"Look, Will, I'm fine! Just tired, but even that is going away." Serena complained.
"I guess I can let you off the hook this time, but you're not allowed to play at the next capture the flag game."
Serena shrugged. "That's fair."