AN: This is an idea I have. Just because MoD!Harry is a favorite cliché of mine, in any crossovers. So until I am blessed with plot-bearing bunnies, this will stay a oneshot to tease you. And me.

When Percy, Hazel, and Frank went to free Death, they never expected to come across someone else. Well, someone who wasn't a monster trying to eat them, anyway. But it was true. Every single being they had encountered since their departure from New Rome was either di immortals or a deity, minor, major, and everything else in between.

But the man currently perching on top of an overstuffed chair (Percy doesn't even want to know how it got there) didn't radiate the feel of the gods and didn't stink of monsters, and was currently holding a conversation with the captive God of Death. Or, at least, was shouting and yelling at the bound Death, while the god himself merely sat still, seemingly at ease.

The trio climbed up the rest of the trek up the tip of the iceberg (and if Frank wasn't afraid of sliding down to the churning Arctic, somehow, then he's a god) and finally gets a clear view of the man.

His black hair was tangled haphazardly as if forever tousled by a breeze, and his skin was fair even against the snow, so that was saying something, which set off his brilliant green eyes. Percy had never seen eyes so like chips of gems; on the risk of sounding nerdie, he'd say like elven beryls from Lord of the Rings, different from his—and every descendant of Poseidon's— sea green. Other than his long, black cloak that was whipping around him making shimmering patterns, and the man appeared to have no discomfort hanging around on a piece of iceberg with plain white shirt and whitewashed jeans.

"—next time you pull something like this, see if I care—"

"Mas—"

"That's Harry to you, bloody idiot," the man cut the god off. "I don't care about your little tiff with Gaea, or Terra, or whatever it is between Romans and Greeks. You're making me do extra work for nothing at all! Why, if Hela—"

Frank dipped his head down to hide his mouth. "Think he's gone off the rocker?"

Percy squinted. "Hmm, no. At least, don't think so."

"Hazel?"

The daughter of Pluto eyed the man warily. "He seems to know what he's talking about, if understating a bit."

"Little tiff with Gaea?" Percy said wryly, and they all knew that if it wasn't so very probable and tied so very closely to their own lives then they'd probably roll around in laughter.

"And he's British," Percy added.

His two companions eyed him with unanimous look of 'and that matters how?'

"Hey, he sounded like that detective guy on BBC!" Percy protested.

"I know my accent is gorgeous, but could you please keep it down? Sleeping giant there."

The three jumped, Percy automatically swinging Riptide and Frank readying himself while Hazel backed down to the rear automatically. She had no Arion, and was compared to Percy no spectacular swordfighter.

The man brought a thin silver rapier which Percy could've sworn wasn't there up to block Percy's swift strike. "Whoa, chill. I'll just wrap things up a bit and then you can have Thany to yourselves."

"Thany?" Frank's jaw was hanging quite unattractively, so Hazel smacked his head down until his upper teeth ground down his lower ones in a painful clack.

The man gestured to the bound god watching the proceeding with blank eyes.

Percy could've listed a great many things about this man that was unsettling him, but near the top of the list was making the God of Death's eyes crinkle in amusement. That was something he could live without.

"You know, Thanatos. I thought you were Greeks… or at least you," the mysterious man pointed at Percy with his rapier. "But I digress—go ahead and free him."

Frank hesitated. "You're not going to do it?" In his opinion, someone who could freely yell at a god—the Death God no less—was bound to be powerful. It will save them a whole Tartarus of problems.

"Nah," the man waved a hand dismissively. "I can't interfere, at this point… but an advice, Frank Zhang," the man's eyes flashed a poisonous, sickly green before reverting back to the warm jade, "sometimes sacrifices doesn't necessarily mean losses."

"That's my line, Maste—"

"If you know what's good for you Thany you'll kindly shut the hell up!" the man barked back at the god. "Don't forget that this whole mess started with you sleeping on duty!"

Hazel really didn't know what to say for that, so she didn't say anything.

The death god visibly sighed. "Now, child of Mars, will you do your duty or not?"

Frank gulped.

The man chuckled, which made Hazel want to spear him with his spatha, technicality aside—Frank's life was not something to laugh at. "Who are you anyway?" She finally asked, withdrawing her spatha. She wasn't really good with her sword—not without Arion—but it'll have to do. They'll manage, just as they always do.

The man's so very green eyes turned to her, and Hazel felt as if she was stripped down to her soul. The next moment, the cheerful indifference face was back and he sniggered. "Way above your pay grade, little demigod."

"And how do you know about us anyway?" Frank demanded, eyes leaving the chained god.

"Oh please," the man waved dismissively. Frank got a feeling that he was used to dismissing people out of his presence. "Practically the whole mythical world is aware of you Greeks, and Romans, and your little quests and Primordials—that's what you call them, right?—and everything. You lot could really use some common sense—and that includes you, Thany, don't think you're off the hook yet!" the man finished with another point at Death God. "So, if you're going to continue your quest, I'll leave a bit help—" the man waved at the massive, glittering, slumbering form of the giant, sending a streak of purple light at the giant—"and if you can get those buried weapons down the ice for your little camp, good for you."

"Wait!" Hazel called as the man made to turn away from them. "I thought you can't interfere?"

The man winked. "A little present for getting Thany out of his mess."

And then he disappeared without a god's customary glow.

The God of Death grumbled. "Now, these chains…"

If Piper didn't know better, she'd say the mysterious man was a sorcerer, the likes of Circe who liked to turn the opposite gender into hamsters from Percy's stories. Alcyoneus was asleep the whole time, gripping Twelfth Legion's golden eagle standard like a baby under a spell. However, since she still has all her normal organs, it must've been something else. Frank had tried stabbing the giant, but the pierced skin of gems quickly regenerated back. Then he'd transformed into a giant of an elephant—which made Percy steam with jealousy—and pushed the slumbering giant past Alaska borders, thus finishing the giant off.

Percy had jumped off the cliff (and made Hazel shriek like a girl) before announcing that there are tons of Imperial gold under the ice. He brought a chariot up and Hazel called Arion, and then Percy and Frank transported as many weapons as they can up the ice and into the chariot.

"This will probably sound weird," Percy started, and Frank and Hazel snorted. "But I think we may have… outside factors in this war."

They were still feasting their victory and the return of their standard, but Reyna insisted on hearing the firsthand account of their quest to Alaska before they were distracted by the partying.

Reyna frowned. "Outside, as in beside us, Greeks, gods, and Titans?"

Hazel nodded. "He didn't identify himself as a god, and he didn't feel like a monster, and he definitely didn't look like a titan…"

"…but he did say he was 'above our pay grade'," Frank finished.

Reyna's frown deepened. "An unknown. What does he look like?"

"Now that I think of it, he kind of look like Thanatos," Percy admitted. "The whole pale, black, tall thing."

"Pale, black?"

Percy shrugged. "You get what I mean." Frank and Hazel snickered.

"So what did he do?"

"That's what's weird," Percy elaborated. "He didn't do anything."

"What?"

Frank nodded. "He was just talking to Thanatos when we arrived. Didn't even try to free the chains," he grumbled, still a bit put out.

"More like yelling," Hazel corrected wryly. "Yelling at the death god about screwing up during duty."

"A higher god, then," Reyna concluded.

"The thing is," Percy rubbed the back of his neck nervously, "he could disappear like a god, but without the whole flashing-and-burning-mortals thing. Though he did say he can't interfere."

"Yet," Hazel reminded him.

"This is getting weirder and weirder," Reyna groaned. "I'd say he's another deity of some kind we're not aware of, though judging by his disposition towards dealing with your quest and his actions, I'd say he's not enemy."

"But we didn't know if he's an ally," Frank concluded grimly. "At least we can count on him not sabotaging our future quests, if he wanted Thanatos to be freed."

Great. An unknown deity tied to Death God.

"We can't do anything now," Reyna sighed. "Let's just keep a lookout."

Neither Percy, Frank, nor Hazel ever met the strange man again during their trip on Argus II to Rome. As in, Italy. They hadn't told anyone—there wasn't really time for that, in between the mess with Eidolons, the Romans on their tails, and various side-quests they really could do without.

That was why, when Percy caught Annabeth being pulled down the pit to Tartarus and fully prepared himself (mentally at least, since all they had was the clothes on their back and Riptide in his pocket) for a field trip across Tartarus and met the black-haired man, this time with a set of wings of pure black feathers not unlike Thanatos', he was considerably surprised.

"So we meet again, little demigod. And you brought a new friend with you," the man said with great humor, eyes twinkling in the darkness of the pit. Somehow, his voice carried through the wind whipping around them, and the blood pounding in Percy's ears.

Instinctively, Percy tightened his grip around Annabeth. "What are you doing here?"

"Paying a little someone a visit long due," the man answered. "And you can call me Harry."

If they weren't falling through the deepest pit in existence and risk losing his eyeballs, Percy would've rolled his eyes. "Great. Call me Percy, and this is Annabeth, my girlfriend."

"Strange choice for a date," the man said, lips twitching. "I know who you are, little demigod, but that doesn't explain you taking a trip down my favorite hellhole."

Percy chose to ignore the little ribbing (and Annabeth tugging rather painfully at his hair) and pointed at the thick strand of spider silk twining around Annabeth's ankle.

"Ah, Arachne," the man sighed. "Unpleasant little lady. Still, that is out of my jurisdiction, so I can't give you any gifts."

"Your jurisdiction?"

"You're not mentioned in any mythology," Annabeth interrupted, and Percy glanced to see his girlfriend pinning Harry with a piercing grey stare. "Or any that I knew of, and I knew a lot."

Harry nodded sagely.

"That is because I, little demigod, am never part of mythology," he winked, and then there was a pause before his wings beat powerfully, and he hurtled down before them.

"I could've sworn he didn't have wings before," Percy murmured.

"What did you say?"

So yeah, this is my half-arsed attempt at MoD!Harry, and there is a hint somewhere in that pile of words above as to Harry's real relationship with the gods. Or death god, for that matter. Anyway, I think this is interesting because a majority of HP/PJTO crossovers feature Harry as a demigod. Well I say a MoD Harry is just as awesome, if not more.