Danny stumbled into Nasty Burger, exhausted beyond reason but unable to go home. Not yet.

No, not because he was too stupid to leave his keys – he could simply go ghost and slip into his room and go to sleep if that were the case. No, it was perhaps more fitting to say that he didn't want to go home. Between Jazz's constant worry for him and his parent's constant cry to dissect him like an insect, there was only so much he could take. He needed to be alone.

He didn't even ask Tucker or Sam to come with him. He only wanted to be alone.

"One burger and a soda," he muttered his order. After paying and getting his food, he sat in one of the darkest corners of the room, wishing that no one would see him but was too tired to try to make himself invisible. Concentrating on invisibility and eating at the same time? Too much work – he'd rather just eat.

He ate almost on autopilot, not really caring what went into his mouth. This night's patrol was especially tiring. Skulker was on his tail again. The hunter was now residing idly in his thermos, but it was still a tiring fight, and Danny still couldn't see why the ghost couldn't just leave him be.

Not to mention Vlad Masters was still bugging him as usual.

His burger was finished before he realized it, and he groaned. Less reason to keep staying here. He took his soda and gloomily took a sip.

It was when the darkness around him seemed to grow thick, shadows dancing and dimming, and he could almost feel it grow tangible. Danny blinked and pushed himself away from the dark, alarmed. What kind of ghost was this, to be able to control the shadows?

The dark swallowed him before he could do anything. He felt the panic rise within him. What was this? What should he do? Then, suddenly, it spat him back out, and he fell into his seat unceremoniously. He wasn't the only one the dark threw out.

There was a kid. He couldn't be older than himself. He was thin, so thin, with dark hair and black clothes, olive skin and bags under his eyes. An aviator jacket was slung on his arm, while his other hand held a sword with black metal. Danny's eyes widened at him. Any other day, any other time, any other person, he'd go ghost immediately and beat the crap out of this kid, who was most likely a ghost too –or not, it felt wrong to call him a ghost– but not this one. No, there was something about him that made his ghost half cower with fear, there was something that whispered to him at the back of his mind that whatever this kid wanted, he would obey, and he was certain that it was his ghost half.

There was something about the kid. He was ancient.

The kid with olive skin turned to look at him, and Danny found himself unable to move as the kid's dark eyes scanned his blue ones. Or were they green? Had he somehow transformed partially? He suspected so.

The kid opened his mouth, and his word washed him with dread. "You should be dead."

He felt his fingers tremble, but he quipped back nonetheless, "You feel like death."

The kid's lips quirked into a sarcastic smile. "Do I?" he asked, sounding almost amused. Danny felt his stomach roll when the kid sat across of him, calmly putting the sword on the table next to Danny's soda. "You don't mind, do you?"

Danny shook his head despite wanting to scream 'I do'.

"Do you know what's good and cheap in the menu?" the kid asked him.

"A burger and a soda will do," Danny answered almost dutifully. He looked down on his own tray. "At least that's what I'd take."

"Good enough for me," the kid said and stood up, going to place his order. Danny almost wished the kid wouldn't go back to him, but he didn't. As much as he made him feel uncomfortable, he was curious. Who was this kid, the kid who had the same aura as the ghosts he fought every day, the same aura as him, yet was not a ghost and was much, much more commanding? He wanted to know. He needed to know.

The kid came back sooner than he expected, and he sat across of him again. Danny watched as he bit into his burger, ravenously eating it and licking his fingers afterwards. While he ate the kid glanced right and left, as if wary of whatever might attack him out of a sudden, but he didn't seem to feel threatened by Danny. If he did, it wouldn't be as much Danny was of him.

"So…" the kid said after he took a sip of his soda, "you aren't dead."

Danny shrugged. "I'm halfway there," he said. With so many people going after him, he was surprised he hadn't turned into a full-fledged ghost.

"You're a human," the kid noted. "But you aren't. You're a mix between two different things… a Halfling."

"Most residents here prefer to call me Halfa, but same difference, I guess," Danny shrugged.

"Ah," the kid nodded. "The Halfa. I've heard about you."

"You have?" Danny asked in surprise. The idea of having someone like this kid having heard of him was unnerving, for some reason.

The kid nodded. "You've made several high ranking officials get some nasty headaches," he said. "You're supposed to have died on that day you were blasted. Instead you changed into half human, half ghost." His dark eyes pierced him again. "You're a lot like us. You aren't supposed to exist."

Danny blinked. "I'm supposed to have died?" he asked, shocked. "You mean I really am half dead already? And, 'like us'? What do you mean, 'like us'? Who are 'us'?"

"I can't really say. Technically you're still a mortal."

Danny's brows furrowed. "Who are you?"

"I got nicknamed 'Ghost King', some time ago," the kid shrugged.

"Ghost King? I know the guy, he looks nothing like you."

"Ah, him," he didn't seem too pleased. "Well you can say that whatever he says, I'll still have more power over him compared to anyone."

Danny leaned back in his seat, suddenly alarmed. "You're not one of those nutjob ghosts wanting to take over the world, do you?"

The kid snorted. "World domination's overrated. I've had enough to handle without getting that added to my plate."

"Oh," was all Danny could say.

The kid flexed his fingers while looking around the diner. "I have to say that your town is one of a kind. The higher ups are worried, but I see no threat here. I've never seen anyone being able to coexist with the dead so easily before. No mortal can interact with the dead like this. The balance is fragile, but it's amazing."

"It's not that awesome, you know," Danny said, almost sulking. "Sometimes I actually think the world's almost ending."

"Happens any other day with my friends," the kid shrugged. Danny didn't know if he should feel relieved that he wasn't the only one having to deal with crazy almost-apocalypse or alarmed that apparently the earth was in constant threat of getting blown up, whether literally or figuratively.

"Well then," the kid stood up and took his soda and his sword. "Pleasure to meet you. Maybe we can meet again someday, Danny Fenton."

"Wha – how do you know my name?" Danny asked in surprise.

"I can guarantee you that you won't be needing to worry about the ghosts, not for a while," the kid said, ignoring his question. "You look like you need some rest."

"Wait – "

"Ciao," the kid turned and left the place. From the glass walls Danny saw him being swallowed by tangible shadows before he was gone.

Danny ran outside and stumbled around, looking for the kid. He ran behind a tree and transformed into Phantom, flying across the city in search of the kid. He didn't find him.

For the next two weeks, citizens of Amity Park were amazed, stunned even, that no ghost was in sight. Some were relieved, some alarmed, some went even as far to make theories that ghosts were leaving because this time, for real, the world was ending. The Fenton couple were elated that they didn't need to worry about ghosts anymore, yet at the same time they were worried because ghost was their whole life. Jazz, Sam, and Tucker were suspicious, pointing that maybe all the ghosts were plotting something big before flooding the town. Vlad Masters refused to say anything in the media, though he came to the Fentons for actual discussion for once, with Danny in particular.

Danny refused to say anything to anyone. He knew that sooner or later the ghosts were coming back, and while they were away he was set on getting as much relaxation as he could get.

When the ghosts came back and wreaked havoc as they complained about a lanky kid in black warning them to stay away from Amity Park, at least for a while, the people who overheard it was surprised – Vlad Masters in particular, who immediately set to hunt down this so-called Ghost King, that some called Prince of the Underworld to no avail.

Danny wasn't surprised.

A/N: first try on a crossover of anything. First try writing in DP or PJO fandom, to be completely honest. Did I do ok?

I was supposed to finish my other fic but I got distracted by this idea so I'm writing it out. I think Danny would feel pretty uncomfortable around Nico if they were to meet because Danny is partly ghost and Nico was able to control the dead (as seen in Son of Neptune, where he forced the Roman ghosts to shut up). Nico, on the other hand, I think Nico will be pretty calm and maybe not so curious because I'm sure the god who deals with dead people (I forgot, is the name Thanatos?) would have informed Hades of this enigmatic kid who is both dead and alive. I also think that Ghost Zone is actually a part of Underworld, so pretty much everyone in there knows of Nico. So they have to do whatever Nico says. Nico can, of course, ban the ghosts from coming to Amity Park altogether, but since ghosts are bound to whatever it is that ties them to the living world I don't think he can ward the ghosts off forever. In here, Nico is supposed to see if Amity Park being so close to Underworld would be too harmful. Let's just say Nico doesn't think it'll be too much of a problem.

I hope you enjoyed it. Please leave a review!