A/N: So, this is a gift fic; yay for gift fics! Rebornhoneybee was the 100th reviewer for A Path Rewritten. Her request was for a Mass Effect one-shot for Fem!Shep and James Vega, their sparring sessions turning into something more. This is my first time writing the Vega/Shepard pairing, so if you like it, I'll consider it a job well done. I felt it might get a little lengthy, and didn't want to keep you waiting too long, so I've decided to post it as a short multi-chaptered piece. I hope that's okay! :D

Background: Shepard did not romance anyone in Mass Effect, or Mass Effect 2.

Disclaimer: I make no profit from this, but enjoy it regardless. Bioware can have their toys back in a bit.

Under My Skin

Part One

After Mars, Kaidan's doubts were beginning to wear on Shepard. They were supposed to be friends, and it was because of that she had let his continuous lack of trust slide; but after Mars, even with him in Huerta Memorial, badly injured, she was furious with him. Sure, she had been working with Cerberus, an organization that had a hell of a reputation for being terrorists, but they had revived her from well, death, and had been the only ones doing anything to stop the Collectors. She had been doing it for the greater good, her reputation be damned. Why Kaidan couldn't see that, why he couldn't trust her, was maddening.

On Mars he'd gone so far as to interrogate her about whether or not she had cut ties with Cerberus, and even hinted that she could have been feeding them information. Her former guard, lieutenant James Vega, had stood up for her against someone who was supposed to be her friend. To say that had stung was a little bit of an understatement.

Vega picked up on it. Quite astutely. After their brief dance of fists, he'd offered her a dance whenever she needed one. And right now – she needed one.

How could she not?

Kaidan had held a gun – on her. Even after she had lowered hers and ordered her own squad – Vega and Garrus – to stand down and do the same. The Major had stood down in the end, and then had the audacity to ask her if he could rejoin her crew aboard the Normandy! In the end, she'd been so livid, so frustrated with him, she had told him to take the position Admiral Hackett had offered him.

He looked so hurt, her subconscious chose to remind her, for the tenth time in the hour since she'd boarded the ship.

Oh like how I must have looked after each time he chose to dismiss me and call me a traitor, she chose to snap back, though talking to herself couldn't be a good sign.

She needed to vent; pacing her cabin, checking and answering messages, a cold shower – not of it had helped. She left her quarters and took the lift down to the shuttle bay, eyes immediately scanning for the premises for the buff lieutenant. No sign of him, but there was at least there was another option. He had a punching bag tied up in the small alcove he'd made for himself and, if she couldn't vent in a hand to hand fight, at least she could beat the crap out of a bag. She stalked over, not bothering to wrap her hands and, raising her fists, went at it. Pound after pound, for what felt like eternity, her body sweating and chest heaving. She was so lost in the experience that she didn't hear Vega sneak up on her, not until he actually spoke.

"You really should have wrapped your hands, Lola."

With a huff, she stopped and stepped back, swiping the back of her hand across her forehead, the sweat stinging the abused skin of her knuckles. Shepard turned to face him, folding her arms across her chest as her eyes roamed over him; the man was massive, even for a soldier, and tattooed, even had the slightest bit of a mo-hawk in his shaven hair. A huge flirt, and cock sure about it; she enjoyed their casual flirting, but it helped that he was so very on the eyes.

"I can take a little pain," she rolled her shoulders in a slight shrug.

He smirked, his warm brown eyes clearly amused. "Kinky."

Shepard couldn't help herself. She laughed, full on belted out a loud laugh. His smirked transformed into a grin and he too laughed. She enjoyed the lighter moment, considering the hell that was outside the hull of the ship; it was hard to forget the Reapers moving through every inch of the galaxy, destroying everything in their path.

"I'm a little on edge," she admitted once she had stopped laughing.

He glanced briefly at the beaten-up punching bag. "My punching bag noticed." He cocked his head and sobered up, just a bit. "The Major get under your skin, Lola?"

She scoffed and frowned. Kaidan had gotten under her skin, but in a bad way; Vega, on the other hand...he made it hard for her to play the indomitable Commander Shepard, made it hard for her to forget she was a woman. It was easier forgetting that little tidbit when she was trying to save the galaxy from annihilation. That was a little bit more important than the attraction she was fighting for her lieutenant. A little bit of the problem was that she didn't want to fight it.

"I don't like having friends who don't trust in me." She unfolded her arms with a soft sigh. "He'll do more good with Hackett, I think. Now - " she rolled her shoulders and stretched her arms out " - I'd like a dance, if you would be inclined to indulge me."

"I'd love to indulge you," he chuckled.

They wandered out the middle of the hangar, the open space having proven many times a reliable sparring ground. He rolled his shoulders and stretched, as she had only moments before, and she found herself watching a little more intently than a commander should. She had to suppress the urge to lick her lips, an action highly inappropriate, even with their rather casual friendship mixed with their little bits of flirting. The Alliance had fraternization regulations, after all, and it was for good reasons; relationships tended to mess with the chain of command, especially in life and death situations – situations Shepard found herself in quite often.

"C'mon Vega, waiting on you," she taunted, lowering her shoulders as she brought up her fists.

"Sexist," he teased, doing the same, "leaving it to the man to make the first move."

"Like you have a problem with that," she laughed, swinging a right hook at his face, which he easily blocked with his forearm. She tapped her fist against his arm, teasingly, before then swinging her left fist out in the same way, which he blocked in the same way. He winked at her. She bounced back on her heels, rolling her shoulders again. "Nothing wrong with liking a man who knows what he wants and knows how to get it."

"Oho, is that so, Lola?" The way he purred her nickname made her shudder and suddenly all her anger at Kaidan – her supposed friend – just melted away. This wasn't about venting, not anymore. Somehow, within minutes of being in his company, he could 'calm the storm', as it were. It had always been that way, even when he had been guarding her on Earth, when she had been under house arrest. And she hadn't exactly been calm, given her situation and the galaxy's reluctance in her belief – substantiated belief – that the Reaper's were coming, and soon.

She smirked. "I like that kind of man." His eyes widened a fraction and she took advantage of the slight distraction, sweeping her leg out to knock his out from underneath him – not an easy feet for someone of her size to do to someone of his size. Lucky for her she had cybernetic implants, given to her by Cerberus when they rebuilt her from the ground up(or really, brought her back from the dead). But Vega was quick, for his size, and dropped his hands beneath him to catch himself, before flipping over once, then twice, before hopping up onto his feet, just in time to block another of her right hooks.

"Underhanded tactics," he muttered, before thrusting her off of his arms and making her stumble. He came at her with a left hook, one she ducked under, before punching her fist into his side, just near his kidney. He grunted and shook it off, grabbing her arm and flipping her onto her back. She sprang back like a cat, on her feet and circling him as he circled her.

"You do whatever it takes to win," she chastised.

His lips pulled up at the edges in what she could only call a sly smirk. Like he had an idea, one she couldn't foresee and wouldn't be able to guard against. That looks made her wary, but she was never one to back down. The adrenaline pumping through her made her tingle, heart pumping wildly, and her back and forth with Vega certainly wasn't helping that.

He came at her and she swung her fist out, but he ducked beneath it, and charged his shoulder into her abdomen, holding her as tackled her to the floor. She gasped as her back smacked against the floor; well, that was the reason she would say she gasped, because it wasn't from the way Vega towered over her, his face mere inches from her own, his own hot body flush against her. Their eyes locked and she refused to believe she was blushing. Determined, she hooked her legs on his hips – ears picking up on his own gasp – and flipped them over, so that she straddled him.

Okay – pretend you don't notice that, she told herself sternly as she felt the bulge against her thigh. He blushed this time, if that was any consolation. And it was. A bit.

"I think that's enough for today," she said, as coolly as she could manage, climbing up off him and extending her hand. He took it and she helped him to his feet; their hands lingered for a moment too long, their eyes locked, and then they both flushed in the cheeks as they took their perspective hands back.

Oh he was getting under her skin. That much she couldn't deny.

As she walked into the elevator, and found herself watching him until the doors slid shut, she realized that she didn't want to deny it.