It had been years.
At the duration of the quest Percy, Thalia, Zoë, and Bianca Di Angelo went on, you had made quick friends with the unclaimed kid, Nico Di Angelo.
But when he ran away when he got news of Bianca's death, you never saw him again. You stayed at Camp Half-blood, while you got news of him being at Camp Jupiter a few years later. He snuck off to go be with Romans, and completely forgot you existed.
Or so you thought.
After the second Giant War, you saw Nico around camp. He looked different. More powerful, paler, and his hair was more shaggy. He never seemed to notice you. Or recognize you. Maybe he just didn't realize it was you.
One day, he seemed to actually see you, and he rushed over, engulfing you in an awkward, but tight hug.
"I missed you.." He said, eyes trailing you up and down, trying to figure out what happened, and why you looked so different, or maybe trying to act like he hadn't changed. After a few minutes, he buried his face against your neck.