Ok! This is a new one for me (amazing right?), but hey that's what prompting is for.

Hiccup/Astrid and Eret/Heather with some swapping (strictly heterosexual no slash here).

The story is ultimately a Hiccstrid fic, but there'll be Heathcup and Eretstrid.

As for the rest... read and see!

-HTTYD-

Sharing a look with her boyfriend as she locked the door of her flat, Astrid was a little stunned. Her best friend, Heather, and her boyfriend had recently left after one hell of a conversation.

To cut it short; the two had invited Astrid and her boyfriend Hiccup to a swinging club. With them. To have sex with each others partners... it had Astrid thrown and Hiccup looked no better.

"So... what do you think?"

Hiccup shrugged absently, fiddling with the little braid at the side of his hair that she had put there. It was a nervous habit of his.

"It wasn't what I had in mind when I suggested a double date, that's for sure."

"Yeah, me neither."

Awkwardness was thick in the air, neither partner totally sure what to say. The thing was... Eret and Heather had been together years longer than Hiccup and Astrid. She and Heather were best friends.

Maybe Astrid was being a little silly by worrying?

"You wanna sleep on it and talk about it tomorrow? Only I got an early shift at the car shop."

Astrid knew Hiccup didn't know what to say any better than she did. So she agreed, and the two got ready for bed silently. Slid under the shared covers of her bed in an equally soundless manner. Hiccup did lean over to kiss her goodnight, but he didn't immediately pull her into their usual spooning position. Astrid almost rolled over to question him - she didn't like the nights sleeping alone when he wasn't at her place or she at his, missing his warmth - when a hand wrapped around her waist.

She was just overthinking. Astrid closed her eyes, enjoying the steady thump of Hiccup's heartbeat against her back and his arm a firm weight around her. Hiccup was probably just tired and that was why he was quiet. Satisfied with her mental reasoning, Astrid slept rather soundly.

Hiccup was back to normal the next morning too, making her extra crispy bacon sandwiches and coffee, kissing her goodbye as he left for work. He was as comfortable in her flat as if he lived there himself. Astrid smiled to herself as she found a post-it note with a smiley face in her lunch for work, much preferring when Hiccup was staying over to grabbing a meal deal from the cafe opposite work when he wasn't.

Heading out to work herself, Astrid caught up with Heather when she got there. Work was where she had met Heather and Eret, already an established couple by then.

"Eret not on the same today?"

Heather shook her head, something in her face tightening before smoothing out into her usual smile.

"Nah. Management decided to separate us more often. Someone probably complained."

Tutting in disapproval as she slipped into her apron, Astrid picked up her trusty pad and pen before heading out to work. Heather worked the kitchen of the pub, Eret behind the bar where respectable alcoholics started as early as ten in the morming. Astrid did the waiting tables, but she enjoyed it. She met plenty of interesting people, recognised regulars and got tipped pretty well for her genial, friendly service.

Plus her boss was chilled out, happy everyone did their job. Wiping her damp hands on her apron to remove condensation from carrying cold drinks, Astrid turned to see how Heather was doing. Her friend was busy serving Bucket and Mulch, two of their regular heavy drinkers who never seemed to actually get drunk. Astrid was quite fond of the mad old couple. There had been the odd scrap with new customers about their openness toward them being gay, but Bucket pushed them and Mulch clocked them around the head.

Problem solved.

"Hey guys, how are you today?"

"Can't complain! Especially wi' these wonderful ales."

Mulch answered, grinning through his massive beard. Bucket was staring off into space as usual, masses of hair escaping from under the metallic helmet thing he wore to protect himself from falling over, which he did alot.

Astrid waited until their break to broach the topic hanging in the air between she and Heather, standing out on the roof littered with cigarette ends and empty coffee cups that escaped the unfit-for-purpose bins. Heather smoked; Astrid liked the fresh air and leaning over the edge to scare passers-by. She blamed Ruffnut for that.

"So... about last night."

Heather looked up from her cigarette, pulling on the cancer stick again and blowing out a long stream of smoke.

"Look, it's not a big deal."

Astrid frowned to herself; it sounded like a big deal to watch Hiccup have sex with Heather. For her to have sex with Eret.

"I'm worried it'll change mine and Hiccup's relationship. Hel, I'm worried it'll ruin our friendship. I love working with you and Eret."

Heather took another puff, then smiled.

"Don't worry. It's not gonna change a thing. Hel, might even bring you two closer, you never know."

Astrid pondered, remembering how she hoped she and Hiccup would last like Heather and Eret.

"You and Eret aren't worried?"

"Nope. We've been talking about it for a while."

Having a little think while Heather finished her cigarette, Astrid watched as steam swirled away in the wind while her coffee rapidly cooled. She trusted Heather... and the longer more stable couple were set on it not changing anything.

"Coming back in? I'm freezing!"

"That's because smoking is bad for your circulation."

"Eat me."

Heather wasn't acting any differently with her for someone who had suggested she would like to swap partners. In the same room. Sexually. Maybe Astrid was reading too much into it. She absolutely needed to have a more in depth chat with Hiccup about it though. Which she couldn't do until they were both home from work.

Hiccup was already at her place when she returned, work overalls tied around his waist and chest bare as he tinkered with her broken laptop. Her kitchen smelled like him, grease and oil and a little smoky... it was sexy as hell and Astrid was generally hard pushed not to just mount him when he got back from work.

"Afternoon milady! Where have you been?"

He always greeted her like that, interested to hear about even the most mundane parts of her day.

"Oh, the usual. Went to work, took over the world and declared everyone my slave. But that was a lot of effort so I just quit, served some drinks and came back here."

Hiccup chuckled, fiddling with the tiny parts of hardware that didn't seem to want to work for her.

"Any luck?"

"Yeah, there's some fried circuits. I think you must have put it down on some water or something... I'll pick up the stuff to fix it in a couple of days when I'm next up that way."

Astrid smiled and rubbed his messy mop gratefully, which Hiccup protested as he hadn't showered yet and he had been all sweaty. She didn't mind, not at all.

"Coffee?"

"I'd love one."

Hiccup had cleared up the mess on her table when she was done busying herself by the kettle, and the view of his lean torso across the kitchen table was as appealing a view as it ever was.

"So... should we talk about the elephant in the room?"

"Snotlout is here?"

Hiccup snorted, laughing at Astrid's joke as he put down his coffee to avoid spilling it in his amusement.

"No. You think I'd be topless if he was? All I'd hear is his insistence on feeding me protein and torturing me in a gym."

"Fair point. So... Eret and Heather."

"I'm guessing you saw them today?"

"Just Heather, Eret wasn't on the same shift."

Hiccup nodded in understanding, taking a sip of coffee.

"Ok. So did you talk to her about it?"

"Yeah. She said her and Eret have been talking about doing it for ages."

"Why us though? I mean I assume these places have other couples they can... trade with."

Astrid stirred her mug, ensuring none of sugar had pooled at the bottom un-dissolved.

"I don't know... trust, I guess? They know us, so it's not as scary a first time as just turning up to have sex with strangers."

Hiccup tapped his jaw with his thumb, a sign he was forming difficult thoughts into words.

"You're thinking about saying yes."

Astrid was very much on the fence, but couldn't deny she had been thinking about it a lot over the last twenty four hours.

"Heather said it's no big deal and won't change anything. I guess I trust her judgement? And they've been together years so they might well know better how it will or won't affect them or us... I think what I'm saying is we try it and maybe it's for us, maybe it's not. Better to regret what you did than didn't experience?"

The little crease between Hiccup's eyebrow tightened in thought as he frowned lightly, then smoothed out.

"Maybe. I guess it's just my own ego giving me problems."

Assuming he meant Eret's ribbing that Hiccup was 'Mr Vanilla', she probed him on it gently.

"How so?"

"Watching you... with another guy. With a guy built totally different to me. Maybe I'm worried you'll like him better."

Astrid got up immediately, crossing the room to curl her arm around Hiccup's head and press it in to her chest. It usually cheered him up.

"I'll never like anyone more than you you dolt. And I'll have to see you with Heather, she's taller and has the whole tomboy vibe and she's not a blonde. But I trust you'll still like me best after."

She wasn't one hundred percent convinced, but letting Hiccup wallow in self-doubt was not an option. He hummed in the back of his throat as Astrid petted his hair, nuzzling her chest and peeking up to see if he was in trouble his face on her boobs.

"Having fun?"

"Mhmm. So... are we saying yes to Heather and Eret?"

Part of Astrid had sort of hoped Hiccup would still be against the idea, which was ridiculous when she thought about it since she was the one who did much of the reasoning. But since he seemed to be on board, Astrid supposed they both were. Mostly.

"Yeah."

-HTTYD-

Hi I'm your author and I don't know how to write a couple broaching this topic. So if this chapter completely sucked... sorry Sq!

But y'all know I'm good for the smut. So hopefully this didn't put you all off.

I'll stop babbling now.