AN—Not exactly what the OP was asking for, but I just kind of took the premise and ran with it. This takes place post-ME3, and the crew is just tooling around the galaxy living large and in charge off the royalties from the vids. I don't know a whole lot about cars, so any gear-heads out there just bear with me when I make a mistake.
A few things to note:
According to Wikipedia, a pony car is an American class of automobile launched and inspired by the Ford Mustang in 1964. The term describes an affordable, compact, highly styled car with a sporty or performance-oriented image.
The songs I was listening to during the driving scene was "Animals" by Nickelback ( watch?v=kUIBHmOwL9o) and "Hey Pretty" by Poe, the radio version ( watch?v=h_lhspmjCJ4).
Garrus eyed the newest addition to the cargo bay with a mixture of curiosity, trepidation, and growing concern. He had no idea where Shepard had found the car but here it was, a throwback to days long past, looking very out of place next to the Kodiak. James, Kaidan, and Shepard all had their heads under the hood and Shepard was gesturing excitedly at the incomprehensible mass of metal. Her tank top and jeans were smeared with oil and she had her hair up in a loose ponytail.
"Look, they even added the new Hummingbird mods to the manifold! This baby is gonna purr like a fucking tiger once I get her out on the road."
Garrus stumbled as he was gripped by a wave of anxiety. "You're not actually planning on driving that thing, are you?"
Shepard turned around and blew an errant lock of hair out of her face. "Garrus! Look, it's a refabbed 1970 Dodge Challenger! There's a company on Earth that remakes classic cars, but it was pretty banged up after the Citadel crashed and I was starting to think I'd never see this thing, but they delivered it this morning." She was practically bouncing up and down in excitement. "It's an exact replica of the original, but I had them add a few mods to give it a little extra kick."
"What are you planning to do with it?" Garrus asked, but he was already pretty sure where this was going.
"I asked Wrex if I could take her out for a spin on Tuchanka—because that is some bitchin' terrain they have out there—and he seemed pretty enthusiastic about it. I believe his exact words were, 'I would like to see you drive one of your Earth death-machines.'"
Garrus' mouth fell open in horror at what she was suggesting. "You can't be serious."
"What? Why not?"
"Because, well, you're not, ah, very good behind the wheel."
Shepard threw up her hands, exasperated. "You aliens, I swear to god. I keep trying to tell you—you may be better in aerial transports but give me anything with wheels and I'll drive it to the moon and back."
"I seem to remember you almost killing everyone in the Mako a few times."
"Oh yeah? When was that?" She crossed her arms and leaned back, awaiting his explanation. Kaidan took an involuntary step back to avoid the fallout.
"That one time we were being chased by that thresher maw on Edolus—"
"Uh huh."
"-and you skidded out and nearly flipped us into the side of a mountain, then you fired a rocket and used the momentum to hurl us over the edge of a cliff."
"I remember that mission," Kaidan said wistfully. "I'd never seen driving like that before in my life."
Garrus snorted sardonically. "Probably because anyone who has died immediately afterwards of massive head trauma."
Shepard held up a finger and said, "So let me get this straight. First I pulled a 180 degree turn at 75 miles per and got us within inches of a solid surface so the thrusters could give us some extra boost. Then, I killed a thresher maw with a rocket to the face and vaulted a tank over a pool of acid that would have eaten clean through the undercarriage, and then I put us back on the straight and narrow to the shuttle with only minor stress fractures to the shocks without giving anyone so much as a case of whiplash . . . and you think I'm a bad driver?"
Garrus was speechless; he had never thought of it like that. He, Tali, and Liara had all spent most of their time in the Mako scared shitless by Shepard's insane tactics (except Wrex, of course—the grizzled old krogan was never happier than when he knew he could die at any moment), but he hadn't taken the time to analyze what she was doing. She was constantly pulling off impossible stunts, but she'd always gotten everyone back alive and in one piece. "Hang on, you mean to say you did all that on purpose?"
Shepard started laughing so hard she had to lean against the bumper to stay upright. "Garrus, that was combat driving. I admit, I may have gone a little overboard sometimes because the way you'd cling to the door was really cute—"
"Cute?"
"—but I knew what I was doing, and I was always in control. The Mako was a tough old bitch; she could handle it."
"You thought me hanging on for dear life was cute?" Garrus asked incredulously.
"Positively adorable," she said with a grin and turned to Kaidan. "You've seen me in action, back me up on this."
"You may not be able to fly very well—no offense—but I've never seen anyone make a tank dance like you did." Shepard pointed at him and looked at Garrus as if to say, See? I tried to tell you.
Garrus sighed (he'd been with her long enough to know when he'd lost) and turned back to the car, the sky-blue paint gleaming in the harsh light. He could just make out the cream-colored interior through the windshield. "Okay, fine, but why this car?"
"I learned to drive on a car like this back on Earth. It was an ancient hunk of crap that was held together by rust, duct tape, and a prayer but I've always had a soft spot for the classics, especially pony cars." She ran her hand lovingly over the fender and smiled. "I've still got to tune her up a bit, but she should be ready by the time we get to Tuchanka. Want to help? You did some good work on the Mako back on the SR-1, and I can't let just anyone put their hands all over my girl." She winked when she said it and wondered how he had managed to fall in love with the craziest adrenaline junkie in the galaxy.
"Sure, why the hell not," he said, certain he would regret it.
They spent the next three days working on the Challenger while Shepard regaled Garrus on the merits of the old muscle cars. "You can take this thing through some tight turns and it'll lean a bit, but it's so wide and low you'd have to really fuck it up to flip it. They're great for road trips—the Shelby's a great one for endurance driving. I opted for the 5-speed transmission—the original only had a 4-speed option—and got the Jakarta fuel injectors so I can really open her up on a straightaway."
They spent a lot of time under the car, head to head while she pointed out all the different parts and made sure everything was in top condition. He followed most of what she said, being somewhat mechanically-minded himself, but her enthusiasm was infectious and soon he found himself looking forward to seeing it in action.
"You know, you should come with me for her maiden voyage," she said as she slammed the hood closed. She put her tools away and leaned on the quarter panel, wiping her grease-stained hands on a shop towel.
"Shepard, I know you said you can drive but I still associate you behind the wheel with mind-numbing terror."
"Come on! It'll be great." She pushed off the car and stood right in front of him, giving him her best puppy-dog eyes. "Please?"
Garrus scoffed and rolled his eyes at the ceiling. "The things I put up with for you." She grinned and planted a kiss on his scarred mandible.
"Trust me, you're gonna love it."
"Remind me again why I let you talk me into this?" Garrus asked, strapping into the seatbelt.
"Because I'm your favorite commander in the galaxy?"
"Oh, yeah." Should have worn your armor anyway, stupid stupid stupid.
"And because Vega's got 200 creds that says I can't get you to scream."
Garrus tried not to look shocked that his friends were betting on this. "That a fact?"
"I put down 300 that says I can."
"I hate you so much right now."
She shot him a shit-eating grin and twisted the key, releasing a loud growl from under the hood. Garrus could hear Wrex shout encouraging things like, "Show the turian how it's done!" Shepard gunned the engine into a roar and dropped it into gear to make the tires squeal. Then all at once she let off the emergency brake and they shot off with a plume of dust and exhaust as she shifted through the gears. Garrus pushed back into the seat and tried not to think about how bad a wreck would be at these speeds while Shepard let out a delighted whoop beside him. The road was so damned close, why oh why had he gone along with this?
"See, Garrus, isn't this awesome?" she shouted over the wind and the roar of the engine.
"You're insane, woman!"
"I'm human, we're not exactly known for our restraint. We invented rollercoasters and bungee jumping, after all." Garrus remembered when she'd told him about all the crazy things humans did for fun and wondered (not for the first time) how humans had managed to make it this far as a species. "Now, what do you say we put this thing through its paces?"
"What are you do—ohsweetspiritspleaseletmeliv ethroughthis—" he wailed as she whipped the car around and started doing donuts, enveloping them in a cloud of dust. She pulled out of the spin, the back end fishtailing wildly, and immediately skidded into a 90 degree turn that had them drifting nearly to the edge of a sheer drop-off. Garrus grabbed onto the oh-shit handle and concentrated on not hyperventilating. No way would he give her or Vega the satisfaction of seeing him passed out.
"God, I missed this! This is better than sex."
"I think I should be offended, but somehow the paralyzing fear is making that impossible." He was torn between wanting to shut his eyes and needing to see it when his death came racing at him, but Shepard just chuckled.
"Oh, come on. It can't be that bad." She spun them around and drove in reverse across the flat open wasteland before whirling back around and gunning the engine hard. "Do you want to know how fast we're going?"
"No!"
"We just topped 85 miles an hour." She put a hand on his leg and squeezed. "She's really heating up now. Just think—before today, this car had never seen the open road. We're the first to open her up and let her loose." Her hand started sliding up his thigh and she pressed down a little harder on the accelerator. Garrus glanced over at the speedometer, which was inching toward 90. He was terrified and exhilarated and very aware of the heat of Shepard's hand on his thigh.
"Cars like this you have to treat like a lover. She'll only run for you if you keep her engine lubricated, and if you try to get too heavy handed with her, she'll stall out." Her hand moved a little higher, and the needle on the gauge topped 92 mph. Garrus' heart started hammering in his chest—between the vibrations beneath him, Shepard's hand on his leg, and the adrenaline rush he found himself stiffening behind his plates despite himself.
"If you know what you're doing you can really make her dance, but you have to ease her into it. Can't just jump straight to fifth gear. You've got to shift—" she inched a little higher and Garrus' breath caught in his throat—"and work the clutch—"she stroked the crease at the very top of his inner thigh—"and make her want to move for you." On the last word she slid her finger up along the slit between his legs and even through his pants the sensation made him gasp. She grinned at him and opened his fly, her lithe fingers moving while she focused her attention on the road. As soon as she got it open she plunged her hand into his pants and stroked his loosening plates.
"Shepard . . . the road . . ."
"I'm watching, don't worry." His erection pushed out from between his plates and she ran her nails lightly up the ridges on the underside, then wrapped her fingers around him and squeezed. He let out a moan and bucked his hips against her hand. The needle was edging into the red, closer to 100 mph. "The inline-six is working hard now, the pistons thrusting faster and faster." She began to pump his cock and he arched his back against the leather seats, pulling against the oh-shit handle as the heat rushed down through his legs and up his spine. Suddenly she took her hand away and before he could protest they were skidding into a sharp turn, the back end whipping around dangerously close to another dropoff, and then they were back on the road again. She took his hand and placed it on the steering wheel.
"Can you steer her for me?" she asked, folding his fingers around the smooth wood. He nodded, and she started stroking his cock with one hand while the other found the sweet spot under his fringe. Garrus growled and fought to keep his eyes on the road as the pleasure flooded through his body. Spirits, this woman was determined to kill him. Shepard shifted closer, leaned in, and licked the back of his neck, eliciting a shuddering groan from him. When her teeth clamped down on the back of his neck he squeezed his eyes shut but when he felt the steering wheel start shaking they flew open again and he had to jerk the wheel to the left to get them back on the road.
"You know, I really loved the Mako. That old tank was amazing, so heavy and powerful." Garrus groaned and gripped the handle above his head so tight he was afraid he'd rip it off. She knew how much he loved it when she used that low, sultry voice on him and breathed along his neck. The sexy little moans she was making every time they hit a bump were doing wonderful things to his insides. "I loved to watch you work on her, your hands deep in her undercarriage . . . tightening her drive shaft."
Garrus' mouth was so dry from panting and he was having a hard time forming a coherent thought as her fingers tightened around him. "Pull over."
"What'd you say?"
"Pull over." She chuckled wickedly in his ear and she took control of the car again. Garrus pulled his pants the rest of the way off and Shepard, in one fluid motion, whipped her shirt off and tossed it in the backseat. She had her pants down to her knees before the car came to a stop and as soon as the emergency brake was on she scrambled over the center console and straddled his lap, the back of her head pressed against the ceiling as she took his face in her hands and kissed him hard enough to bruise her lips. She fumbled down beside the seat, pulled on the lever, and the seat dropped down so they were more or less horizontal. Garrus grabbed her hip with one hand, his cock with the other, and shoved himself into her opening with a growl. She was already soaking wet but still tight and gasped as he filled her, but the feel of all that hard length stretching her wide was absolutely delicious. She ground her hips against him and he thrust into her hard and fast, burying his face in her hair and gripping her shoulders.
"Yes, Garrus, oh fuck-" she moaned.
He huffed out a breath with a loud Huh! and his whole body tensed for one split second that seemed to go on forever before his world exploded into a white-hot supernova as the orgasm crashed over him, bringing her right along with him. Her muscles clenched around him and she squeezed his hips with her knees, clinging to his neck as she came and dragged the aftershocks out of him.
They stayed together, locked at the hips, breathing hard in the cool, dry wind that curled through the open windows. "I think you've changed my mind," Garrus said.
"Hmmm?"
"I love the way you drive." She laughed and lifted herself high enough for his member to slip out of her before settling back into his lap. "By the way, I think you lost 300 credits."
She nuzzled his neck and he could feel the smile that spread across her face. "Totally worth it."
~End