This ended up a lot longer than planned, but here's part two! There will definitely be a part three. I wasn't intending on this part to be so long so I decided to break it up to two parts. Be on the lookout for part three :)

For the record, I do not condone cheating. There could be plenty of reasons why Astrid does what she does. Are they looking to add someone to their bed? Are the polyamorous? Maybe they even broke up. Don't just jump and assume without reading the rest of the story. Don't leave homophobic comments. I can't believe I even had to come back and add this.

Enjoy!

Heather thought she wouldn't be able to look her neighbors in the eye after that first night and she was right. The next day she ran into them on the landing and she had to look away before they saw her blushing. After the first time, she had heard them some more. Either she's been oblivious this entire time, or they've been keeping it quiet until now and just don't care. Heather isn't proud of how many times she's gotten off on listening to them.

A few weeks later when Heather is cleaning her apartment that there's a knock at her door and she pulls it open to see Astrid, hair wet and clutching her jacket around her body. She gave Heather a smile, "Hey! I'm sorry to just drop in like this, but I accidentally locked myself out of my place and Hiccup isn't answering his phone. Do you think I could hang out here until he gets home?"

Heather nodded, taking a step back and waving her in. "Yes, yeah, of course! Come in! Can I get you anything to drink? I have some tea made."

Astrid sighed, relieved and made her way into Heather's apartment. She dropped her bag near the door and took a seat at the table, "Tea sounds great, thank you." Astrid glanced around the apartment, shivering and rubbing at her arms. "and thank you so much for this. I was run-ing late this morning and forgot to grab my keys."

Heather only nodded. She had heard the reason why she was running late this morning. She swears that couple goes at it more than anyone she's ever met. She poured Astrid a cup and set it in front of her, "It's totally fine. You can have Hiccup drop by here whenever he gets back."

"You're so sweet. I can't believe we haven't talked more."

Heather gave her a smile, "I know. We've been neighbors for so long, it's crazy we've never had a full conversation."

Astrid nodded, "Now is our chance, though. It could take Hiccup hours to check his phone." She took a sip of her tea before looking to Heather, "if you're okay with me being here that long, that is."

Heather waved her off, "No, it's fine, really. It'll be fun getting to know you."

Astird's smile brightened, her hands gripping the mug. She sat up straighter, "So, what do you do for a living?"

The two talked nonstop for an hour. Heather had to admit that Astrid was cool. It was easier than Heather would have thought to push what Astrid sounds like during sex out of her mind while the two talked, and she was honestly hoping she wouldn't have to hear them again after today. Eavesdropping on neighbors she doesn't know is one thing, but eavesdropping on a friend is completely different.

It was about half and hour later when there was a knock on her door and she stood to answer it. Astrid was already up and sliding her shoes back on as Heather pulled the door open. Astrid grabbed her bag from the floor, slipping past Heather and pressing a quick kiss to Hiccup's lips. Heather averted her gaze, feeling her face flush at the sight. Astrid pulled away, spinning on her heel to look at her, "Thank you again for letting me in and keeping me company. It was fun!"

Heather returned her smile, "Anytime, really."

She shut the door once their backs were turned and took a deep breath. Shaking her head, she returned back to cleaning her apartment to keep her mind distracted. It was only thirty minutes later that she heard Astrid's undeniable moan. Heather shouldn't be surprised that they're having sex now, but this time it just felt wrong to listen in. She quickly grabbed her car keys off the table and left.

It's a few days later and Astrid and Heather have hung out a few times. Astrid hasn't let on at all that she knows Heather listens in, but if she does know, the girl doesn't seem to care. Heather is sitting on the couch watching one of her favorite shows when the yelling starts. She tilts her head, hoping to maybe hear what their fight is about when it hits her that she hasn't heard them fighting in awhile. They seemed to be getting along a lot better. She wonders what it's about. The fight seemed to go on forever, and Heather wondered if this was one of their worst. A door slammed, and Heather jumped, not expecting it.

A knock at her door caused her to jump again, but she stood, heading over and pulling it open. Astrid was standing there, hair in a messy braid and eyes rimmed red. Heather's eyes widened. Astrid has always come off as strong with an attitude of someone who doesn't care, but she guesses everyone has a breaking point. Hiccup must be hers. She ushers Astrid in, leading her to the living room and offering her something to drink. Astrid gave her a weak smile, asking if she had anything strong.

"Is everything okay?" Heather asked as she handed Astrid a glass of wine.

Astrid hummed, taking it. "I don't really want to talk about it."

Heather knows what's wrong. The fight with Hiccup, but she can't exactly tell Astrid she could hear their fight. That would be pushing a boundary and ruining a new and good friendship. She drops it, pouring herself a glass of wine to go along with Astrid's.

An hour and a half later, Astrid is still curled up on her couch, wine glass clutched in her hand. She hasn't said much. A few words here and there, but not complete sentences or making jokes like she usually does. Heather wonders just how bad the fight was if it caused Astrid to shut down like this. Heather studied the side of Astrid's face while she stared down at her glass, biting her lip as tears brimmed her eyes. She's not blind, she can see that Astrid is gorgeous. Hiccup is a really lucky guy.

Heather reached over, resting a hand on Astrid's shoulder, "I'm sure the fight wasn't that bad."

Astrid's head turned fast, "How did you know it was a fight?"

Heather stuttered, retracting her hand and pulling it to her lap, tearing her eyes from Astrid. Oh no. She hadn't meant to say anything about the fight! "I, um.. I can't think of anything else that could break you down like this."

Astrid stared at Heather's face as she swallowed. Her eyes narrowed and she glared. Heather wasn't a good liar in the slightest, she knows this. Astrid knew it, too, so why did she even try? Heather knows she's an even worse liar when she's tipsy.

"You're lying. How'd you know?"

Heather took a deep breath, dropping her head back against the couch. She could try and lie herself out, but that wasn't working too well for her. Why was she even trying? She turned her head to face Astrid, "I kind of… heard the fight."

"You heard it? What do you mean you heard it?"

Heather gestures to their shared wall, "Thin walls." Astrid's eyes widened as she stared at the wall behind them. "I couldn't hear much, honest, just yelling. It's mostly muffled."

Astrid set her glass on the table, getting to her feet and pacing in front of the couch, her eyes darting to the wall every few seconds. Heather could tell by her face that she wasn't happy, and it was understandable. "You've been listening to us?! If you could hear us fighting, what else have you heard?" At Heather's silence and blush Astird lets out a disbelieving laugh, fingers tugging at the ends of her braid, "Oh my God. Oh my God! You've heard us having sex?! Why didn't you ever say anything or tell us to stop or…"

"You really had no idea that I could hear?" Heather's eyebrows furrowed in confusion, "I thought for sure you would have heard things going on over here."

Astrid was shaking her head frantically, "If we had any clue, we wouldn't…" Astrid took a deep breath, before falling silent, her eyes glued to the wall.

Heather looked at her, raising an eyebrow. Astrid seemed frozen in place and Heather could see the gears turning in her head. "Are you okay?"

"I should be mad. I should be so mad that you would listen to something so private, but I'm not."

"What?"

Astrid laughed, shaking her head and crossing her arms over her chest. "I guess I'm a little bit of an exhibitionist, who knew. Hiccup will be thrilled."

"I… what?" Heather shook her head, making sure she was hearing right. Astrid wasn't mad at her? She thought for sure if she was ever found out for listening she'd be toast, but as it turns out, Astrid… likes it?

"I want to try something." Heather's head was spinning as Astrid kneeled on the couch next to her, tilting her head. "Where can you hear us the most? In here or?"

"Here." Heather nodded, "definitely in here."

Astrid was biting her lip as she stared down at Heather. Has she always looked that good? Since when did Heather feel anything towards another female? The way Astrid was looking at her through was making her feel some kind of way. Was she leaning in? Oh, she is. Should she stop her? Should she go with it? What does she do?

Astrid stopped, lips hovering right above hers. Heather was breathing hard, green glued to blue. Astrid smiled, "Are you okay with this?"

Heather only nodded. She was far more okay with this than she ever thought she would be. Astrid leaned in the rest of the way, pressing her lips against Heather's. Astrid buried a hand in her locks, giving a gentle tug and causing Heather to tip her head back further. Her mouth opened in a gasp, allowing Astrid to slip her tongue in. Heather whimpered, her hands gripping Astrid's waist. It was strange. It was something she had never done. What about Hiccup? The way Astrid was kissing her was something she had never experienced and Heather couldn't help kissing back. Astrid moaned when their tongues met, battling for dominance.

Heather shivered at the sound. It was so close and clear, and Heather adored the sound. It was completely different hearing it near her rather than muffled through the wall.

Sense seemed to come back to her. She gently pushed Astrid away, their lips disconnecting and Heather had to keep from letting her eyes fall to Astrid's swollen lips when she licked them. "What are you doing?"

Astrid raised an eyebrow, "Kissing you?"

"Obviously, but… what about Hiccup?"

Astrid smirked, looking to the wall again. "If you can hear us like you say you can, Hiccup won't mind one bit." She sat back, hands falling to the hem of Heather's shirt. "That is, if you're okay with this."

Heather didn't have to think long. Astrid's… hot. Her lips were swollen from kissing her, her face flushed, and Heather was dying to see what was under her clothes. It was a thought she never thought she would have about another female, but here she was, seconds away from begging this girl to take her. She nodded, "Let's do it."

Astrid only smiled before diving back down to kiss her. Her hands slid under Heather's shirt and ran across her stomach before letting one slide to the hem of her pajama shorts. Heather let her legs fall open as Astrid's hand slipped inside her shorts and underwear in one swoop. Astrid nipped at her lip, pulling away with a smirk, "I didn't think you'd be so into this."

Heather moaned as Astrid's fingers slid down her center, rubbing at her clit, "I didn't think so either."

Her fingers rubbed her clit for a few more seconds before dropping down and letting two fingers slide into her warm, wet center, her thumb pressing against her clit for more pleasure. Astrid hovered above her, watching her face for her reactions. She was loving the sounds Heather made. The small gasps when she would push her fingers back in, and the moans when she hit that spot deep in her.

"How do you like it?" Astrid's free hand slid from her shirt, sliding back up Heather's body, fingers brushing against her neck before gripping her hair again and pulling and earning a loud moan from the black haired girl. "Judging by that, I'd say you like it a little rough?"

"Yes."

"That's what I thought." Astrid curled her fingers expertly in her, hitting that sweet spot again Heather raised her hips for better access, wanting to keep the pleasure going as long as she could, a little worried this would be a one off. Astrid leaned down, working her fingers in her and latching onto her neck, using her teeth to nip before sucking.

Heather's back arched, her fingers digging into Astrid's shoulders, pushing her hips into the hand, riding her fingers. Astrid pulled away from her neck, smiling at the mark that was forming. She let go of Heather's hair, using her now free hand to brace herself on that couch so she could better work her fingers to bringing her off.

Heather's moaning was music to her ears. It was a beautiful sound, and she wanted to hear more of it. Heather let go of Astrid's shoulder, finding the arm that was balancing her on the couch and grabbing the wrist, pulling it towards her neck. Astrid only smirked, letting her fingers wrap gently around her throat and giving a small squeeze.

Heather's fingers tightened their hold on Astrid's wrist, moaning as the feeling of being choked was just enough to push her over the edge. Her legs tried to close around the hand between her legs, but Astrid pulled her other away from her neck, gripping her thigh and keeping them from closing as she fingered her faster, thumb rubbing her clit harder.

Astrid sat up once Heather's legs stopped shaking, pulling her hand from her shorts and bringing her fingers to her lips, sucking the juices from them. Heather whimpered at the sight, tugging Astrid's arm to pull her down and crashing their lips together.

Astrid pulled back, "Let's take this to your room."

Heather bit her lip, nodding and standing on still shaking legs but holding out her hand for Astrid's. "I have something we can use in there."