One: Hum a Song

Roy Mustang strode to his office in annoyance. General Grumman had just handed a mission specifically for him, and while he had no reason to refuse, it pissed him to no end.

He had to go undercover.

With Hawkeye.

As married couples.

And while the general's matchmaking attempts wasn't something that Roy was surprised at anymore (seriously, haven't he ever heard of the freaking fraternization laws?!) and was something that Roy actually found enjoyment in, it wasn't the thing that annoyed him. No, it was the fact that he also want to send Fullmetal with them.

As their son.

And he wanted Roy, of all people, to be the one to tell the two of them.

Oh, Roy could just imagine the rant the boy would give him…

He came closer to the door to his office, and was surprised to see the entirety of his unit pressing their ears to his door. Even Hawkeye seemed to be listening intently, even though she didn't have her ear pressed to the wood. He frowned and asked, "What's the matter with you all? Isn't Fullmetal already in there?"

He jumped in shock when they all hissed and hushed him, and even Hawkeye threw him an annoyed look.

"He's already in, and we're trying to listen to him," Havoc whispered.

"What, is he in the middle of another short rant?"

"No… I think the chief's singing!"

Roy's eyes widened to the size of saucers. Fullmetal, singing? It couldn't be. Immediately, he took a spot on the door and pressed his own ear to it.

Sure enough, there was a soft yet constant stream of tunes coming his way. And it sounded like Fullmetal, too. Roy was surprised – he never thought Fullmetal was even able to sing. The melody wasn't like any song Roy recognized, but it was clear as a glass. He'd almost believed Fullmetal to be a professional singer.

Then a thought hit him and he withdrew from the door. Wasn't he impeding on the boy's privacy this way? Just hearing a bit of the actual song alone told Roy that singing was incredibly important for Fullmetal. No one could fake that kind of fond tone he was adopting while he sang the song. Considering the boy's personality, Roy didn't think he would find it funny if he knew they were listening in. He stared at his subordinates and asked, "How long have it been?"

"Not long," Havoc answered.

"Alright, that's enough," he said. "Get away from the door, now. I have something to tell Fullmetal. Lieutenant Hawkeye, you're coming with me."

"But Sir, he's still singing!"

Roy opened his mouth to tell them how much he cared about that fact (none at all, the level of how much he cared was so abysmal that even the most ignorant would cry) and that they had a job to do so get to it, never mind how hypocritical that statement was. He never did manage to do that.

The sound of stomping steps emanated from inside the room, dulled only by the leaves of the doors. They swung open quickly, pushing the eavesdropping soldiers away, and revealed the boy in red that was not only red in the clothes, but also in the face.

"What the hell are you doing in here?" he demanded.

"Listening to you, Chief, that was some beautiful voice you have there!" Havoc replied cheekily without missing a beat.

"Why were you – haven't you ever heard about privacy?!"

"Hey, you were the one who sang, it's not our fault that it's loud enough for us to hear," Breda returned, shrugging with a smirk.

Any other time, Fullmetal would have seen the contradiction in that statement, since they were clearly eavesdropping instead of simply hearing the singing without meaning to, but apparently the boy was too frazzled to reply. His face burned so red that Roy thought he'd passed out. Still, that kind of reaction nudged at him and he couldn't resist giving his own jibe.

"Why, Fullmetal? Were you scared you'll shatter all the glass or something?"

Havoc and Breda tried (and failed) to stifle their laughs, while Fuery and Falman coughed into their hands and Hawkeye stared, disagreement in her eyes mixing together with something akin to mirth. It was a joke, and they all understood. There was no way Fullmetal's voice could shatter glass, unless he was screaming shrilly about his height – or lack thereof.

If it was even possible, Fullmetal's face went even redder. He looked down to his feet, shuffling, and for a moment Roy thought he really was going to pass out.

"It was private," Fullmetal's voice was quiet, but it held a silent warning. It struck Roy, then, that the act of singing itself might be something that Fullmetal associated with something painful. He sobered up at once.

"Alright, now, back to your work," Roy told his unit. "This has gone long enough. I'm surprised you didn't stop it, Hawkeye."

Hawkeye pursed her lips, seemingly ashamed of herself. "Apologies, Sir."

"Go back in, Fullmetal, I've got a mission I need to discuss with you." He turned to face Hawkeye. "You too, Lieutenant."

Fullmetal's face slowly went back to its normal shade, much to Roy's relief. He stepped aside as Roy and Hawkeye walked in and closed the door. "What mission?" he asked, following Roy to the couch. "Why do you need to discuss it with Lieutenant Hawkeye too?"

"Well, Fullmetal," Roy began, sitting down on the couch as Fullmetal did the same across of him while Hawkeye stood ever so loyally behind his couch, "this mission is a bit special. General Grumman himself gave it to me."

"Really? Is it really that important that he needed to give it himself?"

"Apparently. And all three of us have to go there and handle this."

He couldn't see Hawkeye, but he got the general feeling that she was frowning. Fullmetal, himself, didn't stop before asking, "Wait, what exactly is this mission about?"

Roy sighed. "This mission requires us to go undercover."

"Right, and…?"

The sigh was heavier this time. "Hawkeye and I need to pose as a couple, apparently."

Fullmetal's mouth formed an 'o' while his hand shot up to point at them. Surprise was clear in his golden irises, then after a moment a hint of mischief mixed into it. He grinned smugly at them, clearly pleased at the general's idea of undercover.

He could hear Hawkeye gasping behind him. He closed his eyes and took a deep breath. Even though she was surprised, he knew Hawkeye would take it well. She was professional, almost scarily so. So it left the harder part to deal with. "That's not all," he continued, and Fullmetal's attention was drawn to him once more, though the grin still rested on his face. "You're coming too."

Fullmetal blinked, the grin fell. "Wait, what am I supposed to do anyway?"

"You're going to pose as our son."

The face Fullmetal made was priceless. His jaw hung open at once without showing any signs of closing on itself anytime soon. He stared speechlessly at Roy for a long while, as if all words he had ever learned had puffed into smoke from the tip of his tongue.

"I'm supposed to go as your son," he said when he finally found his voice. "And you're gonna be my dad. And Hawkeye's my mom." His voice trembled like a feather in the winds, and Roy could tell he was trying hard to keep his calm. He waited for the inevitable rage to come.

It never came.

Fullmetal simply slumped in his seat, eyes wide with surprise and disbelief. He stared at the faraway wall, muttering a small 'huh' without showing any sign that he was going to blow up. His reaction was as explosive as a limp, gasless balloon. Then he turned to look at Roy, eyes unreadable, asking, "What case is it about? And can I bring Al?"

As Roy explained the case and told Fullmetal that Alphonse couldn't come as much as he himself wished that the armor could, he couldn't help but notice how Fullmetal seemed to be calmer than usual, how he listened with attentive silence as he took in all words that came out of Roy's mouth. Strange how he seemed to be content on the opportunity to go on this mission. It was almost as if he was looking forward for it, even though he was clearly dejected that he was unable to be with Alphonse or that his research would be temporarily halted.

Almost.

But Roy didn't dare to hope. Instead, he hoped that this mission would go without a hitch and that everything could go back to normal as soon as possible. He ignored the blooming feeling in his chest, the slight giddiness in his feet and flutter in his stomach, almost as if he, too was looking forward for this mission.

Almost.

Roy decided to chalk it up as anticipation for any kind of challenge the case might present to him.

When he sent Fullmetal away to pack his belongings and get ready to hop on the train to tackle the case, he caught the faintest hum in the air that sounded suspiciously like Fullmetal's voice. Remembering how the boy fluster and panic when he realized the unit had been listening to him singing, Roy couldn't help but wonder what song it was, and if he could get the opportunity to listen to him again.

Perhaps, if (when, he hoped) Edward was more comfortable around him, he would get an opportunity to hear the boy sing for real.

A/N: apparently I need a constant dose of parental!Royed stories. Sigh.

Right, so this will be a collection of one-shots featuring parent-child relationship between mainly Roy and Ed, though there will be some parental!RizaXEd and Royai too. Each one-shot will be interconnected with each other. All will feature the three of them during their undercover period. I have no idea what the case might be and why they have to undercover as a family, and frankly I don't really feel like expanding it beyond a series of interconnected stories like this, mainly because I want to focus on my other ongoing fic. Darn, I'm supposed to have updated it...

Anyway, this is it for now. I hope you enjoyed it.

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