Here is a little Ed/Roy fic I wrote. I wrote it out and self beta'd it in about half an hour, so apologies for any mistakes.

Disclaimer: If I owned Fullmetal Alchemist, then Roy and Ed would be canon.

Blondes Have More Fun

"Shit." swore Roy, pushing back on the thick shaft that was driving between his ass cheeks.

"You . . . can't do that . . . now," grunted the blonde striving atop him, auto mail hand groping Roy's left pectoral. "And I'll . . . kill you if . . . you try."

"Ha," the older man laughed joylessly, as much as he enjoyed their 'meetings', Roy wouldn't call sex 'joy' until he'd pounded enough alcohol to subdue a small elephant.
He groaned as one of Ed's hands left the taut flesh they'd been massaging to trail down the spread cleft of Roy's abused ass. How Ed had talked him into this he couldn't remember, and with the next push of Ed's turgid cock into his insides, he didn't care: Fullmetal had found his volume control and that was all that mattered.

He let out a long, tortured moan as Ed's thick self drew away from the sensitive area, pulling out almost completely.

"So there it is, finally." Ed spoke into his ear, voice low and evil.

"Just get on with it," Roy glared into the golden eyes of his subordinate, almost surprised when the younger boy's lips began to manoeuvre his own. The other alchemist's hand dropped to the older man's erection, meandering a teasing finger up Roy's solid length.

"Not really in any position to be bossy, Colonel." whispered the boy, making his rank sound like something Christian parents feared. "Maybe I should stop, walk away right here, leave you all naked and needy, tied to your desk with no release."

Roy was tempted to head butt the blonde. It was all he could do in his current state of being completely dominated. God, he thought, if the boy wasn't so damned sexy. . . .
Roy knew that if he retaliated then Ed really would leave him. Hell, he'd probably call Riza in to help him too.

"Or maybe," he murmured, biting Ed's shoulder just so, making him release the moan that he himself was so close to making with those skilful hands on his member. "You should keep pumping yourself in, hit my sweet spot a few more times, and we can both get on with the day." He kept his voice low and sexy, praying the blonde would relent.

Roy returned to the area on the boy's shoulder that he'd bitten, he sucked hard on the flesh, effectively marking Ed. He felt a dribble of precome come off the end of Ed's dick, perched teasingly just barely inside.

For God's sake, he'd never tortured the boy like this, why did the younger get to have all the fun?

And just like that, Ed was inside again. Angling himself perfectly to hit Roy's nerves every time. He captured Roy's lips in a messy kiss, rubbing his metal hand faster across the older man's hardness.

They moaned simultaneously into the kiss as they came to their respective climaxes.
It was Roy who exploded first, white rain painting the blonde's chest. He felt the tremors in the other's cock as Ed's saltiness warmed his insides.

"You know, Fullmetal, you really are an irritating brat sometimes."