Author's Note:

Main Pairing: Harry Hart/Gary "Eggsy" Unwin

Side Pairings: Mycroft Holmes/Greg Lestrade, past Mycroft Holmes/Harry Hart

Warnings: Mild language

Disclaimers: The world and characters of Kingsman: The Secret Service belongs to various peoples who are not me. Sherlock belongs to the BBC, Mark Gatiss, and Steven Moffat. The original characters are the property of Arthur Conan Doyle. I own nothing but the plot and make no money from this story.

Eggsy had dragged Harry into the café after demanding to be fed. Harry, as the good boyfriend he was, had tutted but allowed the tugging, had even smiled when Eggsy held a seat out for him. He did sigh softly when Eggsy said, 'What, can't pull the chair out for me boyfriend?' Harry disliked the word "boyfriend", claiming he was far too old for such a label. But Eggsy used it, so Harry just had to deal.

'How's yeh sandwich?' Eggsy asked through a mouthful of chips. They were damn good. Eggsy hadn't eaten since dinner the night before, having spent most of the early morning and afternoon at Headquarters helping train (read: scare the crap out of) the new recruits. They had to replace six agents, having lost half a dozen during the Valentine's Day Massacre. Eggsy loved scaring the twenty recruits they had.

'Adequate,' Harry informed him, making Eggsy scoff and nudge his foot under the table. He was wearing his Adidas Wings, and enjoyed the annoyed look Harry gave him when his trainers brushed against Harry's highly-polished Oxfords.

'Fair enough,' Eggsy grinned brightly. Harry's eyes narrowed, but his lips were tilted upward, the older man fighting a grin; Eggsy counted it as a win.

They fell into shop talk after that, skimming over various problems at Headquarters, the amount of missions Eggsy had taken since becoming Guinevere, the amount of paperwork Harry had been slogging through since becoming Arthur... they couldn't talk openly, what with being in public and all, but Eggsy loved the way they skirted around the issues, using codes and made-up names and anything else they could to confuse and trip the other up. Eggsy had just told Harry that he and Rox had "refurbished Mr Trevelyan's kitchen real nice" when Harry paused mid-sentence and sat up.

'Harry?' Eggsy questioned.

'Mycroft,' the man replied, which made no sense, and Eggsy was about to say so when Harry stood and walked around the table.

Eggsy twisted in his seat just in time to catch Harry beaming at some bloke in a three-piece suit before his partner hugged the man and patted him on the back.

'Harry Hart,' the man said. They were the same height- looked roughly the same age, too- and wore their suits impeccably. If Eggsy hadn't met all the Kingsman, he'd have thought that this bloke was a knight.

'Mycroft Holmes,' Harry replied, still smiling brightly. 'I haven't seen you in quite a while.'

'Yes, yes, I've been busy,' the man- Mycroft- said. 'Running Britain doesn't give one a lot of holiday time,' he added.

'As I've learned,' Harry sighed, finally stepping back, putting the tiniest bit of space between him and Mycroft.

Eggsy's eyes narrowed.

'I heard that Kingsman was at the heart of the Valentine matter,' Mycroft murmured. 'Six agents?'

Harry nodded. 'We have over a dozen recruits, and we're trying not to rush them but our active agents need the break. I'm hoping to have six new agents on duty within three months.'

'Are any of them showing promise?' Mycroft asked.

'Quite a few,' Harry said, nodding again, 'but it's a tad too early to tell. Some of them surprise you during their last few hurtles.'

'I remember,' Mycroft chuckled, which had Harry laughing, and Eggsy shifted uncomfortably in his seat. He'd never seen Harry this... friendly with anyone apart from Merlin. And even then he and Merlin spent half their time bickering like an old married couple.

Harry finally seemed to remember that he wasn't alone, and Eggsy threw him a short scowl before looking at Mycroft.

'Oh, my apologies,' Harry said. 'Mycroft, this is Gary Unwin, otherwise known as Guinevere.'

'Guinevere?' Mycroft mused, his light blue eyes rolling over Eggsy's body... his gaze was lazy, but his eyes were shrewd. Eggsy nodded as Mycroft's eyes darted up to his, cool and calculating. 'Mycroft Holmes,' he introduced himself.

'Eggsy,' Eggsy replied.

When Mycroft raised an auburn eyebrow, Harry said, 'A nickname. He prefers it over Gary.'

'Hmm...' Mycroft hummed, 'I've never been fond of nicknames.'

'When your mother names you Mycroft, how could you be?' Harry teased.

'As clever as always, Galahad,' Mycroft drawled. 'Or should I say Arthur?'

'So you heard,' Harry said.

'But of course,' Mycroft smirked at the other man. 'Nothing happens within Kingsman without me hearing about it. Anthea still keeps it touch with Gareth.'

'Of course she does,' Harry sighed. Eggsy must have looked super fucking confused, because Harry retook his seat and gestured for Mycroft to join them. 'Mycroft was a Kingsman agent for a number of years, and his current assistant was a candidate before she joined Mycroft,' he revealed, making Eggsy glance at the auburn-haired man again. He was soft around the middle, middle-age and inactivity making him weaker than your average Kingsman agent. But there was power there, skills retained from years of repeating them... and he was carrying an umbrella, like Harry was so fond of.

'Right,' Eggsy grunted. 'Which knight was you?'

'Percival,' Mycroft replied, not batting an eye at Eggsy's grammar. 'I left Kingsman when a better offer presented itself.'

'You mean when the Queen wanted you working within the government to keep things running smoothly,' Harry corrected.

Mycroft just smiled pleasantly, and Eggsy wondered if that was true. He remembered the times Merlin and Harry both had offhandedly commented on a government contact they shared...

'Harry,' Mycroft said, bringing Eggsy's attention from his thoughts back to the conversation, 'was Guinevere the only codename available? Or is it a comment on your relationship with young Gary?'

Eggsy bristled at being called young and Gary, but neither Harry nor Mycroft were paying attention to him. He scowled at Mycroft, and then at Harry when his partner said, 'There were a number available. Eggsy was brought into Kingsman just before the Valentine mess. He was promoted after I healed and took the mantle as Arthur.'

Mycroft raised an eyebrow, apparently waiting for something else. Harry huffed.

'Yes, yes, alright,' he muttered, 'get it out of your system, Mycroft.'

'I'm just astonished that you would sleep with a candidate when you got so annoyed at me for doing it years ago,' Mycroft chuckled. 'And you and I were both far younger when I was an active agent.'

'I don't believe in mixing my work life and personal life,' Harry said.

Eggsy snorted at that, and the older men both turned to him. 'What?' he grinned. 'Sorry, bruv, but yeh fucked up there, yeah? Merlin's your best mate, you're datin' me, and Roxy's seen ya walkin' 'round in that robe you're so fond of. Pretty sure your personal life and work life 'ave mixed at this point.'

Harry sighed. 'Eggsy, please.'

'What?' Eggsy questioned.

'Don't call me bruv,' Harry drawled, like he always did, voice so offended that Eggsy couldn't contain his laughter. He stuffed some chips into his mouth to try and stifle the noise, failed pretty spectacularly, and smiled widely at Harry when the older agent looked at him.

His face was fond, though, unable to hide how much he adored Eggsy. It'd been that way since he woke up in hospital, once again surviving something that should have killed him. Eggsy had been more shocked than anyone when Harry had requested his presence, and had then attacked his mouth as soon as Eggsy got close enough.

Eggsy had thought he'd spend months pining away until growing a pair of balls and planting a big ol' kiss on Harry's mouth. Harry had beaten him to it.

'Oh, Harry,' Mycroft drawled, making Eggsy and Harry look away from each other, 'really?'

'Really,' Harry echoed. The look he gave Mycroft was pointed and Mycroft's lips curled up.

'I thought you would remain a bachelor forever,' Mycroft commented. 'Isn't that why we broke up?'

Eggsy choked on his mouthful and Harry had to pat his back as he tried to clear his airway. He even offered his cooling tea, and after Eggsy had swallowed half the cup he grunted, 'What?!'

'I take it that you don't discuss past lovers?' Mycroft queried.

'Not particularly,' Harry sighed. 'Eggsy, it was years ago.'

'Youse two dated?' Eggsy demanded as he glanced between them.

'On and off for a number of years,' Harry admitted. His eyes were on Eggsy, wary, like at any moment Eggsy would snap and... something. Eggsy had never considered himself a jealous man... at least not 'til he'd had to watch Harry on a honeypot mission about three months after Harry had been cleared for duty. Thankfully the man rarely left Arthur's office these days.

A jealous Eggsy was a manic Eggsy.

Or so Roxy said.

Eggsy didn't see how threatening to murder someone in the grocers for pinching his boyfriend's arse was manic.

'I was only with Kingsman for four years,' Mycroft added. 'When I left it was as a friend.'

'I didn't want a serious relationship and Mycroft did,' Harry told Eggsy. He leaned over to brush his hand over the sleeve of Eggsy's jacket, fingers digging into his forearm briefly.

'Right,' Eggsy grunted. He took another sip of tea. 'Right.'

Harry eyed him carefully before turning away, while Mycroft just kept on staring at Eggsy in amusement. Eggsy scowled at him, which did nothing more than make Mycroft smirk before striking up another conversation with Harry.

Eggsy just sat back and watched, gaze darting between the two older men as they chatted. He could see the history there; in the lingering glances, the fond looks, the way Mycroft touched Harry's hand and Harry flicked Mycroft's wrist in rebuke for a smart comment. He couldn't stop imaging a young Harry and a young Mycroft fighting side-by-side in their Kingsman-issue suits, umbrellas up and guns held tight in their free hands. Couldn't stop imagining Harry and Mycroft going at it because apparently they'd dated on-and-off for four goddamn years.

Eggsy didn't say a word, not even when Harry excused himself to use the bathroom; it was Mycroft who broke the silence.

'You don't like me,' he said, sounding more entertained than anything else.

'No, I just...' he trailed off when Mycroft looked at him. Eggsy huffed. 'I don't know you, do I? How can I 'ate you?'

'Easily,' Mycroft said. 'I was intimate with your current partner, and from what I can tell you're a jealous man.'

'Am not!' Eggsy denied.

Mycroft smirked. 'It would be unwise to lie to me, Mr Unwin.'

'Why's that?' Eggsy asked.

'I was very good at my Kingsman job,' Mycroft said, 'and I'm very good at my current job. Look up my file, when you get a chance. I'm positive that Merlin would be happy to show it to you.'

Eggsy huffed and picked up a chip to chew on.

'Harry and I are old friends,' Mycroft continued, 'but believe me when I say that I don't think of him like that any more.' It was Eggsy's turn to look at Mycroft, face practically screaming "fuckin' bullshit!"Mycroft pressed his lips together before saying, 'Yes, Harry is still an incredibly attractive man, but I very much don't want to revisit our old relationship.'

'Yeah, right,' Eggsy chortled. 'Have you seen Harry? He's sex-on-legs! He's the hottest person I've ever set eyes on! All he's gotta do is look at me and I wanna drop to me knees! Ya shoulda seen 'im when we first met! 'e just stood there in 'is suit with his brolly and fuckin' looked at me and I wanted ta-'

'Not that this isn't fascinating,' Mycroft interrupted, eyebrows high on his forehead, 'but is there a point?'

'Harry's hot!' Eggsy practically shouted. It earned them more than one odd look, and Eggsy flushed while Mycroft hummed.

'I am aware,' he eventually said.

'And yeh tellin' me yeh don't wanna shag 'im?' Eggsy demanded.

'I don't,' Mycroft said, voice dry.

Eggsy opened his mouth to reply- because everybody wanted to shag Harry, alright? He was fucking gorgeous- but Harry chose that moment to return from the bathroom. Eggsy's mouth shut with a click and Mycroft gave him a sly smile before pulling Harry into another conversation. Eggsy resolved himself to sitting on the sidelines again, jumping between smiling brightly at Harry, giving Mycroft the evil-eye, and feeling Harry up under the table. Harry had just slapped his hand away for the tenth time when their lunch date was once again interrupted by a bloke in a suit.

Eggsy glared up at the silver-haired man, and if Harry had slept with this one, too, Eggsy was totally gonna shoot Mycroft with the dart in his watch.

'There you are,' the guy sighed, 'how long have you been here?'

'Fifteen minutes, give or take,' Mycroft said, smiling apologetically up at the man. 'My apologies.'

'I was waiting outside like a damn idiot,' the man huffed. 'Couldn't have texted me?'

'Sorry,' Mycroft repeated and stood.

Eggsy's eyes bugged out when Mycroft kissed the bloke, then smiled at him when he pulled back, linked their fingers together.

'Gregory,' he said, 'I'd like you to meet Harry Hart and his partner, Gary Unwin. Harry and I used to work together.'

Harry smiled and shook the man's hand, saying, 'Pleasure,' when he let go.

'Nice to meet you,' Gregory smiled. 'And please, call me Greg. I hate Gregory.'

'The only nickname I've ever heard Mycroft continue to use is "Merlin",' Harry commented.

Greg clearly had no idea who Merlin was, but he just smiled and looked at Mycroft. 'Still have time for lunch, or are you needed back at work?'

'I told you earlier that I have three hours free for lunch,' Mycroft said.

Greg grinned at that, a grin Eggsy was very familiar with; it was the shit-eating grin he wore when he locked Harry's office door and draped himself over Harry's desk.

'Good,' Greg said. 'Did you wanna leave now, or...?' He looked at Harry and Eggsy, clearly asking if their lunch was over.

'Yes,' Mycroft said. 'Harry, it was lovely to see you again, but I have to go.'

'Understandable,' Harry smiled, eyes glinting like they did when he knew something you didn't want him to know.

Mycroft sighed and said, 'A pleasure, as always. Mr Unwin, it was wonderful to meet you.'

'Yeah...' Eggsy said slowly. Okay, so... Mycroft really had meant it; 'cause the looks he was giving Greg? That dopey how-did-I-get-so-damn-lucky look? That was what Eggsy looked like every time he stared at Harry for more than forty seconds. 'Yeah, Mr Holmes, it was good meetin' you, too.'

Mycroft smiled properly at that and shook Eggsy's offered hand.

'We should have dinner sometime,' Harry said.

'Yes, we should,' Mycroft agreed. 'You can tell me more about how you and Gary got together.' Harry sighed very lightly and Mycroft smirked. 'Have a good afternoon, gentlemen.'

'Bye!' Greg called as he was tugged from the café, one of Mycroft's hands sitting possessively on his hip, the other clutching what Eggsy just knew was a Kingsman-issue umbrella.

Eggsy sat back down and toyed with his chips, while Harry glanced over the menu, no doubt wanting another cup of tea.

'So...' Eggsy said, breaking the silence. Harry "hmm"d. 'You don't have a thing for young chavs,' Eggsy said. 'It is just me.'

Harry sighed, this time loudly. 'Eggsy...'

'You used to shag stuck-up little tits,' Eggsy grinned. 'Who was the bigger gentleman? Did you and Mycroft fight over who's shoes was the most polished? Did yeh fight over which one of yeh had the most perfect suit? Oh, oh! Did yeh fight over who had the best manners? Did-'

'Eggsy,' Harry interrupted. His eyes were narrowed behind his glasses, but Eggsy just beamed back at him. 'Enough,' Harry eventually continued. 'Yes, Mycroft and I... dated, for lack of a better word. It was only ever casual, and we parted amicably.' He went back to the menu, brown eyes down and half-hidden behind the frame of his specs. Eggsy went back to his chips. 'Besides,' Harry sniffed, 'I am clearly the better gentleman.'

For the second time that day, Eggsy choked on his chips, only this time he was laughing. Harry was clearly not amused.

It just made it that much funnier.

End.

Author's Note: I saw some Sherlock/Kingsman stuff on Tumblr, basically saying that Harry and Mycroft were old friends. I can so see that, but I can also see Mycroft and Harry having had a thing in their younger days, so... this was born. And there's Hartwin and Mystrade, of course, because I love them.

So... that's it. Yup. This was weird, don't really know what it is, but there we go.

Cheers!

{IBegToDreamAndDiffer}