Some people might think that sex on the hood of a car might be uncomfortable, but they would be utterly and completely wrong. The lines of the Camaro molded to Sam's back perfectly – the way the hood sloped down to meet the upward thrust of the windshield, the way the glass tilted at just the right angle for him to lay back and look up into Mikaela's eyes as she pulled away the cotton barriers between them and lowered herself, inch by inch, until they were as close as two human bodies could be. The glass was just cool enough against his back to offset the heat of her breasts on his chest as she leaned down, hands pressed against the glass, to fill his mouth with her hot, sweet taste as she moved, thighs flexing, up and down and brought him ever closer to the edge of something so much bigger than himself, than either of them, than the universe could ever hope to be.
The way his back shifted against the glass just felt so right, the way he slid along Bumblebee as Mikaela slid along him, and Sam didn't know if giant alien robots could have sex or even jack off but in the back of his mind he really, really hoped that Bumblebee could derive the same sort of Oh my God this feels like dying in the best way possible that Sam could feel, bucking up against the girl of his dreams and back down against the not-really-a-car that had saved his life so many times that the soul within his body no longer belonged solely to him but also to Bee – and to Mikaela, the steady force of her light pulling him away from the dark as she'd refused to let him go.
Mikaela riding him from above, Bumblebee's strong, lithe lines beneath him, and Sam Witwicky was in Heaven. Surrounded by the only two beings in the world – in the universe – that could possibly understand what it was like inside of his head, what it took to make him complete, and he was safe and warm and Oh God, never, ever let this feeling end.
But of course, it was over all too soon – hot, wet gasps of I love you and Fuck, Sam! in his ears and the rumbling of Bee's alien engine below him and Sam was over the edge in no time, screaming out a wordless cry as the world dissolved into white static the likes of which he'd only known on the hot desert sand when he was dying, dying, gone –
But then he gasped for breath, came back to life and Mikaela was limp on top of him, breathing heavy, legs on either side of his waist and pressing him onto the hood of the Camaro that was still rumbling, purring contentedly as Sam clenched one arm around her waist and spread the palm of the other hand, wet and slippery, against the windshield behind him. He needed to touch the both of them, so he could lose himself in them and never wake up, never be just Sam Witwicky alone again, but be with them, a part of them, forever and ever and they would never be apart.
Because choosing just one was a choice he couldn't make – he refused, body and mind, to look at one over the other when the feeling in his gut that surrounded their names on his tongue was exactly the same. Because why, in the fight to become whole, should he have to give up one third of the equation? Was it so hard to believe that Sam Witwicky's soul came in not two, but three pieces, that all fit together in a perfect harmony of being that he never, ever wanted to be without?
Hours later, cooling in the too-small backseat of the Camaro with the windows down and the A/C blasting (because things like that didn't matter when your car wasn't a car but an alien robot with an unlimited supply of power and no greenhouse gas emissions to speak of), he wound one arm around a girl's waist again as the other pressed flat against the leather of the seat. Mikaela shifted and murmured warmly against him, her long legs stretching over the armrest and the gear-shift while his were bent at the knee, feet resting against the leather of driver and passenger's seat, touching as much of his car, of his Bee, that he could reach.
"I love you," Sam Witwicky said aloud, and not one, but two voices, high and low in unison, answered the words with their own.
And that was the way it was supposed to be.