Nico is a neko, which are very rare, and are captured for money. Nico is a special neko, too. He can shadow travel, since he is a son of Hades, but he doesn't know it yet. That makes people want to get him more, so he has to hide that he's a neko. Until he finds a place called Camp Half-Blood, which is safe. He still keeps up the act, but while he's there he meets a son of Apollo named Will Solace. He has a crush on him, he doesn't want to admit it, though, and wants to tell him his secret, but doesn't. Will finds out by himself.
Credit to @percabeth1010 for the cover edit.