A/N: EVIL LEO, MWUHAHAHAHAHA! Inspired by a post on tumblr (as usual), this was gonna just be a one-shot, but I decided to make it a bigger, multi-chapter fic. So, here's the first chapter.

Song: 'Thanks for the Memories' – Fall Out Boy

July 14th.

Dirt Face was getting on Leo's nerve. She'd spent every waking hour since Percy and Annabeth fell whispering lies in Leo's ear. She wouldn't shut up. Her voice got louder when he slept, and all chances of nice, dreamless sleeps were destroyed. She plagued his dreams with visions of the Argo II in flames, with Jason and Piper being felled by giants, with Hazel being sucked into the ground and suffocated there. He woke every night screaming for it to stop.

To escape from the horribly vivid dreams, courtesy of Gaia, he stayed awake for days at a time, refusing to rest and working himself to the bone. He didn't smile as often, and spoke less. Twice, he'd been so exhausted he'd passed out at dinner. The second time he'd done that he'd woken up to a face full of pizza and Piper shaking him by the shoulders.

The others shot him worried glances. And, more recently, they'd taken to staying away from him. His exhaustion would make him really crabby. Any disruptions or distractions while working and he would snap. He even yelled at Hazel, and earned himself a black eye; a gift from Hazel's creeper half-brother, Nico.

After that particular incident, he stayed mostly in the engine room or up on deck, talking with Festus. He preferred the engine room, as the noise of the engine was sometimes loud enough to drown out Gaia's annoying voice. When Leo finally met the damn woman, he was going to rip her vocal cords out himself. He'd never been so annoyed before in his life.

Yet…

Some of the poisoned words Gaia whispered rang truth. The others did talk about Leo behind his back. They didn't trust him. Leo took a guess that the reason Hazel and Frank shot him so many resentful looks was because they knew he had opened that damn fortune cookie knowing he would have to sacrifice something. And that sacrifice had been Percy and Annabeth. They hated him for it.

He hated himself for it.

Two weeks after the Tartarus incident, Leo found himself sitting on the floor of the engine room, leaning against the steaming, creaking, groaning old thing, fiddling with several differently sized bolts. With a lack of sleep came a lack of inspiration, so he finally chucked the bolts aside and crossed his arms over his chest. He sat alone for a long time before the door finally swung open and Piper and Jason fell through, lips locked together. The fell against the wall, fencing each other's tongue, before Piper noticed Leo sitting on the floor, glaring at the two of them, and pulled away from Jason.

"Sorry," she said, turning slightly pink. "Didn't realize this room was taken."

"Not anymore it's not," Leo muttered. "See ya."

He got to his feet and stomped out of the engine room, taking care to slam the door behind him. One other thing that got to him: he was alone. Everyone else had each other. Piper and Jason were together. Hazel and Frank were together. Nico hung around with Hazel and Frank a lot. They'd each formed their own tiny groups, and Leo was left alone. The Seventh Wheel, Nemesis had once called him. Always alone.

Leo marched to his cabin and slammed the door. Inside, he flung himself down on his bed, trying to get the image of Jason and Piper swapping spit out of his head, but it was a horribly vivid image.

So here we are, Gaia laughed, all alone again.

"Go away," Leo growled.

Come now, Leo. I'm the only one on this gods-forsaken ship that has been nice to you.

"I wouldn't call keeping me awake for days being nice."

You did that to yourself.

"Because you keep giving me nightmares!"

No need to shout, Leo. Don't want to worry the other anymore, do you?

"They aren't worrying at all."

I guess that is true. They don't care.

"My point exactly."

Why do you stay with them if they don't care? Why do you cause yourself grief for no reason? Leave them and join me.

"That escalated quickly."

You should have joined me long ago, Leo Valdez. You should have joined me before you freed Hera, before you started the war.

"That wasn't me!"

The Romans don't believe that. They'd rather have yours and everyone else on this ship's heads. Fighting on my side will secure your survival.

"Sure."

Leo Valdez, this is a one-time offer. Refuse and I shall be forced to kill you if we ever meet. You could be my best lieutenant. Your ability to control fire could secure you a place in my new world, once your friends are dead and gone. And, who knows? Maybe I'll bring your mother back.

Leo sat bolt upright in his bed. "What?"

Esperanza misses you dearly, Leo. She likes Elysium enough, but would rather be with you. I shall bring her back for you, Leo, but only if you join me.

Leo's palms were sweaty. Gaia had taken his mother from him as a child. The goddess had brought gorgons and eidolons out of death and placed them back into the world. Could she actually do the same with a person?

He shook his head angrily. "No. Stop it. Stop manipulating me and get off of my ship."

Think on it wisely, Leo Valdez. You think yourself one of the seven, but you will never be recognised. Always the seventh wheel, always left out. Always overshadowed. The others will receive fame and glory, should they succeed, but you shall always just be known as the mechanic, the one who steered the ship. The one who sent his friends to Tartarus.

Leo's fists clenched, scrunching up the smooth sheets of his bed in his hands.

Should you decide to join me, travel to Mount Vesuvius. Meet Khione there by the 18th of this month, or I shall take it that you decide to oppose me rather than stand with me.

For the first time in weeks, she fell silent, and she did not trouble Leo for the rest of the night. Instead, he troubled himself.

Meeting Khione… Despite her snobby personality and her hobby of making ice statues of the people she did not like, the goddess of snow was one mighty fine girl. Meeting up with her would be quite nice, even if it was for some dreadful reason.

Leo wanted to stay with his friends. He cared about them all. He didn't want to leave them alone with his ship (which would be destroyed in a matter of seconds if Jason or Frank were at the helm). But, at the same time, he knew what Gaia had said was true. All he was good for was fixing things. Nico could summon the dead; Hazel controlled everything under the earth; Frank could turn into whatever animal he wanted; Jason ruled the skies; Piper could get anyone to anything she wanted; Coach Hedge could instil fear into the hearts of the most terrifying monsters. Leo, meanwhile, could talk to machines and fix their boo-boos. A problem with a machine? Leo was your man. Want to go into a battle head-first with a strong leader who has awesome super powers? Avoid Leo at all costs.

He should've known better than to let Gaia's words get to him like they were, but the only reason he was letting her affect him was that he knew what she said was 100% true and nothing but the truth.

He turned over in his bunk. Gaia's words about bringing his mother back were swaying him horribly. Goddess of the earth… She'd brought souls back before, yes. Who's to say she wouldn't bring his mother back?

She guaranteed his safety after it all ended. He could be safe, his mother would be alive and hey, who knows, he might even sway Khione into his favour.

As for his friends, if he could even call them that; he couldn't care less. They always left him alone anyway. Even if he was felled in battle fighting for Gaia – or even fighting for them! – they wouldn't care. They'd mourn a little, get over him, and forget him. Their world would carry on spinning. He'd be a memory. Nothing more.

Screw them all.

July 18th.

He'd offered no explanation as to why he wanted to land in the Bay of Naples, right near Mount Vesuvius, other than to restock the ship's supplies and give the guys a chance to stretch their legs and take a long, romantic (ew) walk around the city. Jason and Piper were the first off the ship, disappearing into the crowd almost instantly. Nico left with Hazel and Frank – most likely to keep an eye on them – while Leo was left on the Argo II with Coach Hedge, who was watching some boxing program from Britain.

Leo sat on the supports along the side of the ship, legs dangling over the edge. Strapped to his back was a black duffel bag filled with all the supplies he'd brought with him on the Argo II. Mount Vesuvius loomed in the distance. Khione would be waiting for Leo at the bottom, waiting to see if he would join her.

He cast one last glance back at his ship. For a moment, he just thought about what he was doing. He was abandoning his friends, his family back at Camp Half-Blood. He was joining the enemy. He'd be just like that Luke Castellan boy Annabeth had told him about once.

"Screw you guys," he growled, and leapt off the side of the ship into the sea.