Author's Notes: Hey guys! Man, am I tired lol. I really wanted to finish this today and post it because I just loved the idea of where this stemmed from. So this one comes from the Star vs the Forces of Evil Headcannons blog on tumblr and I thought the concept was pretty cool. I'll explain the original concept in the author's notes below, after you read the story just so that there won't be any spoilers lol. And I will admit, I rushed a bit on some parts and maybe later I'll go back and just add extra stuff in.

But for now, enjoy the fic! (Note: This one-shot is technically a headcannon, not an AU)

"Watch where you're aiming, 'princess'!" Marco snarled to the girl behind him as a blast of magic flew past his shoulder and hit the monster in front of him.

The girl, Star, looked at him in annoyance and tucked a strand of hair behind her ear before turning around and aiming her wand at a different monster.

"How about you get out of the way next time, Safe Kid!" Star retorted as she charged up another beam of magic.

Marco and Star had never really liked each other. Star, with her wild and adventurous attitude, didn't get a long very well with Marco, him wanting to be safe and cautious most of the time. They were almost polar opposites. So, when they first met, they both became instantly annoyed with each other. To make things worse, they were forced to live in the same house with each other since Star came from another dimension and needed a place to stay. Her parents had unknowingly picked the only household that harbored one of the only people Star didn't get a long with. Not to say she absolutely hated it however. Marco's parents were always nice to her and she admired them. She was only annoyed when Marco was in her presence, which oddly enough, was often. Marco was also in a similar situation as he's usually a fairly nice person but got easily annoyed when Star was in his presence.

But somehow, they had dug deep down within themselves to tolerate one another's existence when fighting Ludo's minions. They still threw insults at each other, but at least they were doing something as a 'team'.

"Me? You're the one in the way! I would've taken them all down 5 minutes ago if you weren't here!" Marco taunted as he punched another monster square in the face.

"Ha! I would've taken them down 10 minutes ago if it weren't for you always blocking my blasts all the time!" Star snickered as she blasted the last conscious monster with a beam of butterflies and hearts.

Marco scoffed as he turned around to look at her and crossed his arms. "Yeah right! That's a lie and you know it!"

Star turned to face him and placed a hand on her hips, ignoring the dazed bodies of monsters sprawled on the grass around them. "Oh please! Anyone with half a brain could see that you're always getting in the way!"

Marco growled and walked towards her until he was standing right in front of her. "Oh yeah, because you can control the wand so well," he said sarcastically. "I bet you're parents sent you here just for fun then!"

Star fumed and poked his chest. "Shut up! At least my archenemy isn't some 10 year old kid whose apparently a higher belt than you!"

"For your information, that's only because his parents PAID for it! And by the way, your archenemy isn't much better. Ludo over there doesn't even fight; he just gets his dumb minions to fight for him!"

"LUDO MIGHT BE SUPER LAME BUT AT LEAST HE ISN'T AS LAME AS YOU TRYING TO ASK JACKIE OUT!"

"HEY!" Ludo growled. "What do you mean-"

"SHUT UP!" Star and Marco yelled at him at the same time before glaring at each other again. Ludo whimpered before gathering his minions and opening a portal back into his castle. He realized he did not want to be in the middle of this fight.

"I'VE TOLD YOU THIS BEFORE! IT'S PART OF MY PLAN!" Marco shook her fist at her.

Star laughed and blew hair out of her face. "Yeah right, your 'plan'. Like nodding everyday for years is going to get her to like you. I bet she's tired of you and thinks you're super lameee!"

Marco gasped. She did not just say that. "SHE. DOES. NOT! If she thought I was lame, she wouldn't be returning my nods!"

Star snickered. "I bet she probably pities you."

"JACKIE WOULD NEVER DO THAT!" Marco shouted at her. Even as he said it however, there was that little doubt in his mind that maybe, he really did have no chance with Jackie. But he definitely wasn't going to let Star insult him and get the better of him. "SHE'S NICE AND PRETTY AND SWEET UNLIKE YOU!"

"DID YOU JUST CALL ME UGLY?!" Star shouted back at him, clutching her fist. She shouldn't have cared about his opinion, but for some reason, it aggravated her.

"YEAH I DID! NOW I CAN SEE WHY A DEMON FROM THE UNDERWORLD WANTED TO DATE YOU! I BET HE SEES A LOT OF POTENTIAL IN YOU AS PRINCESS OF HELL!"

Star's throat went dry. She remembered the time when she dated Tom, and she had to admit, it wasn't her best idea. He was easily angered and a jerk to her which led to them quickly breaking up. She wanted very badly to retort Marco, but as much as she hated him, there was no way she was going to defend Tom.

"O-oh yeah?" Star stammered "Well you're a-"

"A what huh?!" Marco's voice dared her to say something.

"A-" Star started, desperately trying to think of something.

"A?!"

"A MEANIE!" Star bursted out, a few tears threatening to fall, but willing herself not to. She didn't want to give him the satisfaction of her crying that she thought he would take advantage of. "YOU'RE THE MEANEST PERSON IN THE WHOLE UNIVERSE!"

Marco felt a slight pang to the heart as she said that. He couldn't pinpoint exactly why, but he really wanted to prove her wrong. "M-me? Mean? You're-you're the one whose been mean to me ever since you got here! You always get us in danger and all I do is try to get us out of it!"

"You're always too safe and you keep trying to hold me back!" Star said, eyes stinging. "You're so scared that you'll make a mistake, you don't even want to try anything new!"

"Like what?!" Marco challenged her, his eyes starting to sting as well.

"LIKE TRYING TO BE MY FRIEND!" Star impulsively let out.

It was quiet for a moment, as the two teens looked at each other in surprise, both not believing what Star said. They didn't know how to react at the sudden outburst, and both kind of confused on to what it implied.

Star wants to be my... friend? Marco thought.

I want to be his... friend? Star thought.

"That-that was just an example!" Star scoffed unconfidently as she turned away from him, a blush threatening to cross her face. "Like I would ever want to be friends w-with you!"

Marco snapped out of his thoughts and also turned away from her, trying to hide the fact that his face was turning red as well. "Y-yeah! We couldn't be friends if we tried!" Marco laughed nervously.

"Being fr-friends? With you? Pfft. We're nothing alike, we-we h-h-hate each other!" she stuttered on the word hate. She was now trying more to reason with herself than anything else.

Marco was the same as he nervously agreed with her. "I can't even imagine a world where we get along! It's ridiculous! I bet if there were other universes with different versions of us, we would still hate each other!"

"Haha yeah. I couldn't imagine a world where you and me were actually friends," she tried to tell herself more than to Marco.

That was when a portal opened up a few yards away from them.

Star and Marco caught sight of the oddity and momentarily forgot their conversation they just had a second ago to stare at the portal.

"What the-" Marco started.

Suddenly, two figured emerged tumbling out of the portal. They looked oddly familiar. One was a latino boy with light brown hair somewhere in his teens wearing a red hoodie. The other was a blonde girl also in her teens with pink hearts on her cheeks, holding a magic wand, and wearing a sea green dress with a picture of an octopus in the middle. That was when Marco and Star realized what they were seeing. It was... themselves.

"Owowow!" the other Marco yelped as he rubbed his head. "That was a close one Star. That monster almost caught us!"

The other Star smiled and adjusted her headband that had gotten tilted as they were rolling out of the portal. "Butttt it didn't! And wasn't that fun Marco?! I told you the Jungle Dimension would be a blast!"

Marco rolled his eyes as he patted his jeans and got up. "I guess it was pretty fun," he smiled as he offered a hand to Star. "But... let's just stay home for the rest of the day. I'm feeling like watching some movies on TV. Sounds good to you?"

Star took his hand, pulled herself up, and gave him an excited nod. "Ooooo yes! We should watch one of those... what do you call them? Rom-coms?"

"Uhhh, I was thinking more of a monster movie with a lot of smashing and karate chopping," Marco said making a chopping motion in the air. "That's way more entertaining."

Star put her hands together and tilted her head in an adorable way before putting on her best "Marco please do this for me" face. "But we watched so many of those yesterday! Can we please watch a romcom today? Pleaseeeeee?" Star stuck her lip out and whined. She loved monster fighting as much, probably even more, than Marco did, but she thought a change in the kind of movies was in order.

Marco gave her a small grin and patted her head. He was very fond of her. "Sure Star. Whatever you say."

"YAY!" Star squealed in delight as she engulfed Marco in a tight hug and started rubbing her cheek on one of Marco's cheeks affectionately.

"Starrr," Marco complained (not really) while blushing. "What did i say about hugging like this in public? People are going to get the wrong-"

Star noticed the stop in his voice and turned her head to see where he was looking at. "Huh? What did you say Marco-"

That was when the Marco that came out of the portal spotted the other pair of Star and Marco. The two who had just been arguing a few seconds ago were now staring at the pair of themselves that had just come out of the portal, mouths agape. It was very awkward as the two stared at the other pair of best friends a few yards away from them.

"W-w-w-WHAT?!" The Marco and Star that hated each other yelled at the same time.

"Starrr, what did you do?" The Marco who had come out of the portal asked fearfully as he looked down at his best friend who was still clinging onto him.

"Uh," Star started as her eyes darted between the other pair. "I think I brought us into a different timeline dimension."

"Wait, so these guys are us but in some different timeline?!" Marco exclaimed as he gestured to the other Star and Marco who were freaking out. Sure, they were surprised at the other dimensional them appearing out of nowhere and had many questions, but seeing how the other them were acting with each other made them realize something that scared them to no end. Not only were they good friends in another dimension, but were they were also...?

"Th-this can't be happening," the current dimension's Star chattered to herself. "N-not only are Marco and I friends, but we're also-"

"Th-this can't be happening," the dimension's Marco also said. "N-not only are Star and I friends, but we're also-"

The pair of best friends who still had their arms around each other, looked at their counter in confusion. Why were they freaking out so much?

"Maybe we should ask what's wrong," Star whispered.

"They're probably just shocked to see us," Marco whispered back. "I'm pretty shocked myself." Even as he said that though, they were freaking out a little... too much. As if something was terribly wrong with the other dimensional Star and Marco.

"Well it can't hurt to try," Star said.

"I guess so," Marco agreed with the idea and spoke up. "Hey! Uh are you guys-."

"YOU GUYS ARE DATING?!" the first Star and Marco yelled in sync at the inter dimensional Star and Marco. "BUT... YOU'RE US! TH-THERE'S NO WAY YOU GUYS COULD BE D-D-D-DATING!"

"...Eh?" the Marco and Star who were best friends looked at each other, caught in surprise at the sudden outburst of the question. They then realized their arms were still wrapped around at each other.

"N-no no we're not!" They both blushed as they separated from each other. "Wh-what gave you that idea?!" Marco stammered. "We're just friends!"

"Yeah right me!" the other Marco stomped up to him, nerves fried. "No one acts like that in public and aren't dating! Now tell the truth! in your universe, are me and Star," he choked on his words and blushed even deeper. "D-d-dating?!"

"No no no no no!" Star waved her arms frantically. "We-we're just besties that's all! We hug each other all the time!"

The other Star looked like the world was being pulled out from underneath her. "In another universe, I hug HIM?!" she pointed at her sworn enemy, the confused and dazed Marco. "But- don't you hate Marco?!"

Star blinked. "Why would I hate Marco? He's been my best friend ever since I got to Earth!"

"What?!" the dimension's Marco promptly interrupted, "In our world, we hated each other ever since we met!"

Inter-dimensional Marco spoke up. "Whoa, whoa, whoa. Star might get a little crazy sometimes, but there's no way I would ever hate her."

Inter-dimensional Star nodded as well. "Yeah, Marco might be a bit too safe sometimes, but that's just him, and I love him for it!"

Inter-dimensional Marco looked at her with wide eyes as a blush crept on his cheeks while the other Marco looked like he had just witnessed a crime.

"SO YOU ARE DATING!" he accused in horror.

"W-wait! I didn't mean it to come out like that!" Star stammered, all the while blushing herself.

"Ok everyone, STOP!" inter-dimensional Marco shouted, still flustered but also confused. All four of them grew quiet to hear what he had to say. "Can we please just calm down, and explain what's going on to each other?!"

The dimension's Star and Marco looked at each other before agreeing. They recounted their tale of how they had met and hated each other at first sight. They told their counterparts the things that usually went wrong when they were near each other, they always argued, they were constantly annoyed with each other, and they couldn't stand each other.

"-and she never appreciates me helping her, she's always so annoyed-" Marco rambled.

"-he hates everything I do, he refuses to even listen to what I have to say-" Star also continued on.

They rambled on and on about things that they didn't like about each other and how there was no way they would ever be friends. There was something odd though as Marco and Star continued to listen to the other pairs story.

"Wait hold up," the inter-dimensional Marco stopped them. "If you don't like each other so much, then why do you always hang out with each other?"

The pair blinked. "What? Are you crazy?! Why would we hang out with each other? I have way better things to do than hang out with her!" the other Marco said.

"Yeah!" the other Star agreed.

"So why would you hang out with each other then?" other Marco raised his eyebrow. "From what you told us, you guys always hangout with each other, like us."

The other Star nodded in agreement to her Marcos statement. "Yeah! You guys hang out with each other as much as we do!" she said gripping her Marco's arm.

Star and Marco shouted at the same time. "What?! No we-"

That was when they realized, they really did hang out with each other all the time. They were with each other when they were at home instead of just staying in their separate rooms, at school they still hung around each other, their insults more like teasing, they sat at lunch together, walked home together bickering as always, they did everything together. They were practically each other's best friend, except they didn't want to admit it.

"...don't?" Marco and Star looked at each other as they both ended on the same word quietly. The other Marco was right, there was no denying it. From the moment Star had came to live with the Diaz household, they were never separated from each other for a long period of time. The thought was new to them and it made them both wonder,

Are we... friends?

"Maybe," Star commented. "You guys should, try to get along more? Just look at me and Marco! We're practically inseparable!" she said as she gave Marco another heartfelt hug.

Marco smiled as he returned the hug. "Well, we got to get back our own dimension. I think we'll just let you guys be."

The other Marco and Star nodded slowly, as they were still staring at each other, trying to figure out what to say. The inter dimensional Marco and Star smiled as they looked at their two counterparts. If their counterparts were anything like themselves, they knew that things would definitely turn out all right. They cut open a portal back to their own universe, and stepped inside. The portal closed taking Star and Marco back to their own universe, and now leaving the other Star and Marco staring at each other, not really sure on what to say.

"So..." Marco started, turning his head a little away from her. "I guess that, um, maybe I can get too cautious sometimes," he admitted.

"-And I guess i get a little... carried away sometimes," Star turned her head slightly, as not to face him.

It was a little quiet for a moment, and it the lack of arguing was really eating away at the two. This was one of the very rare times when they were together and didn't argue, and they weren't really sure what to do now except taunt the other to stop the awkwardness.

"Ha!" Star exclaimed as she turned her head to face him, an unconfident smirk evident on her face. "I can't believe you thought they were dating! We might be friends in some other universe but there's no way we were d-dating!"

Marco turned to her with a bewildered face. "Hey! Don't try to hide the fact you were thinking the same thing too!"

"Yeah right!" Star scoffed as she flipped her hair. "Who would want to date you? You probably wouldn't have the guts to kiss a girl anyway!"

Marco glowered at her and took a step towards her. "Oh yeah?!"

Star looked back at him fiercely and took a step closer. "Yeah!"

"Oh yeah?!" Marco shouted and took another step closer, now right in front of her.

"Yeah!" Star shouted back as she met his gaze.

"OH YEAH?!"

"YE-mfff!"

Star stood there in shock. Before she could comprehend, Marco had grabbed her face and pulled her towards him, kissing her right on the lips.

They were both blushing a deep shade of red as they shared the kiss. Marco had his eyes shut tight repeating to himself that 'it was only to prove her wrong' while trying to ignore the butterflies that were fluttering in his stomach. Star was wondering to herself why she hadn't pulled away from him yet... and why she felt her body move on its own and kiss him back. The world was spiraling out of control for them today as they shared their first kiss with the person they thought hated them the most, each other. But yet, hate wasn't really the word for it. In truth, ever since they met, they had secretly wanted to become friends with each other. They understood each other very well and had each other's backs during a battle, even if they were arguing the whole time.

At last, after a full minute of kissing, Marco abruptly removed his lips from Star and backed away, heavily panting. Star was also heavily panting but for some reason, missed the warmth of his lips.

"S-s-see?!" Marco stammered as he tried to ignore the tingling of his lips. "I-I told you I c-c-could do it!"

Marco pulled up his hood on his hoodie and shoved his hands in his pockets. He turned towards the house, away from Star, to cover his blushing face. "I-I'm going inside!" he announced before speed walking into the house, unsure of what he was going to say when he next saw Star or what he would do about his sudden urge to kiss her.

star stood there alone in the middle of the yard for a moment, lightly touching her lips to make sure her lips weren't actually on fire. The thought of Marco was suddenly appealing to her, and prompted her to smile widely. She was surprised that a smile was on her face after just the thought of the person she 'hated' ever since they met. But at the same time, she realized that they both knew, deep down inside, they never really hated each other.

Maybe... they even...

Star skipped towards the home, a new agenda in mind. "Ohhh Marco!" she sang brightly. "I have a few questions for you!"

Boy, was Marco going to get the teasing of a lifetime.

Author's Notes: Haha hopefully that wasn't too confusing. I found it hard to write about two Marco's and two Star's at the same time. It was just kind of annoying to describe which one was which. Anyways, the original idea was that the original concept of Star and Marco would be fighting and Marco would say something mean to Star and she would be on the verge of crying. He would be saying something like "If other dimensions did exist, we would never be friends in any of them!" or something like that and right as he says that, the canon Star and Marco hop out of the portal, hug, and now have to explain themselves. I really liked the idea but I tweaked it a bit to make it where Star and Marco didn't like each other but Star was still an actual princess from another dimension. I don't think I did a good job with the idea but if anyone else wants to do one just like it, it would be awesome if you did (and send it to me so I could read it). Anyways, cheers for now and thanks for everything! I'll see you all later!