If there's one thing Nico tries not to think too hard about, it's Percy Jackson.

Of course, the problem with that is – well. Percy Jackson. Nico's pretty sure that if you say the guy's name three times into a pool of water, he'll crash into the scene chased by three giants, a titan, and his girlfriend.

(He tries that, when the word first goes out that Percy is missing. Nico doesn't look too closely at the thought that it would have been worth the trouble to get him back, because he tries not to think too hard about Percy Jackson)

The point is, Percy's the kind of guy that's difficult to get out of your head, especially when he goes missing without a trace. Even when Nico had hated him, his thoughts had tended to stray in that direction, wayward sheep that he just couldn't herd back into place. After he'd grown up a bit and accepted that maybe everything that went wrong in the world wasn't the son of the sea god's fault, that tendency had only gotten worse.

Not that it's all he thinks about, obviously. Nico's obsessions lean more towards family, his sister(s) and trying to impress his father. He practices, he trains, he wanders in every place because he belongs in no place. And if he's wandering a lot, it only makes sense to look for Percy while he's at it. The world's hurtling towards the edge of a cliff again, bringing in the guy who held it up last time is probably a good idea.

Plus, a son of Hades can never earn too many brownie points

That's all.

(That's not all, and he knows it's not all, but what is he supposed to do about it? The months go by and Annabeth looks more drawn and more determined by the day, and there's no competing with that. He doesn't want to compete with that. And on the days when he thinks that he does, when he starts to consider the possibilities of a Percy without memories – because children of Hades can be kind of assholes sometimes – he forces himself to drop by Camp Halfblood. Reports that there's no word, makes himself watch the way Annabeth sags a little more, because that's love, and what he feels—)

Nico tries not to think too hard about Percy Jackson. He drops by Camp Jupiter to visit Hazel, and tells himself that's the only possible reason, outside of his liaison duties. He doesn't hope, doesn't let himself even think. And he is, in fact, so very successful at this, that when Hazel says she's made a friend (a child of Pluto with friends?), the possibility doesn't even occur to him.

Nico looks up, and there he is. Taller now, broader in the shoulders, but still with that stupid messy hair. Still with the sea-green eyes, still with the stupid face. For a second, Nico just – forgets. It's on the tip of his tongue to say I know as Hazel introduces them, because Percy Jackson is standing in front of him and what the fuck is he supposed to do with that information?

He sticks out his hand. "Pleased to meet you." It's either a lie, or a very simple way to put an extremely complicated truth. "I'm Nico di Angelo."

Percy scowls, and Nico can't figure out if he wants to kick him or – something else. He tries not to think about it. "I – I know you."

And despite everything, despite all his best efforts, something electric sparks in Nico's chest, races through his body.

He thinks he preferred it when he hated the guy.