Falling in love with your best friend didn't work the way it did in the movies or on TV.

Not for Marco Diaz, anyways. There was never a point in their relationship where he was so busy mooning over Star that he couldn't notice any other girl, and he never had some grand epiphany about how she was in love with him that suddenly made him love her too. There was never really a 'friend zone' between them, and falling in love had never been a grand show of romantic drama.

Instead, it was more like breathing. Something so natural and instinctive that you hardly even think about it while you're doing it. Like the way he had gone from freezing up every time she threw her arms around him for a hug to already reaching to return her embrace with one of his own as soon as she leaped at him. Or how her laugh never failed to bring a smile to his face, and suddenly he wasn't so shy about dancing in public anymore whenever he was dancing with her. It wasn't so much that he became obsessed with her or anything the way he had been with Jackie, but before long spending time with her became the highlight of his day and Jackie was more of a distant fond memory, like a silly celebrity crush he'd daydreamed about marrying. All of the stories he told people stopped becoming about things he did or saw or learned on his own, and began starting with 'Star and I.' She made him happy, drove him crazy, and gave him a reason to look forward to every new day.

And much like breathing, he didn't realize just how much he needed her until suddenly she wasn't there anymore.

First there was Mewberty, which had been an awful experience in a million different ways, the cherry on the cake being the way he watched helplessly as his best friend vanished into the clouds, seemingly never to return. Then after that was the chaos of Princess Smooshy's attempted face theft. Then the disastrous Blood Moon Ball and Tom swooping in to try and lure Star into his seductive trap. Every time something came along that nearly took Star away from him, Marco would practically go into a blind panic to bring her back home. To return things to 'normal' and reclaim his best friend for himself, the way that a drowning man starved desperately for air.

And each time things did go back to normal, his feelings for Star went back to being the effortless, instinctive and ever necessary part of his life that he hardly ever noticed or gave much thought to. Those brief close calls were always scary, but nothing ever came from them. Star would always be by his side, and he would be by hers. Always.

Or so he thought.

The grim fact of the matter was that after a while, Marco actually forgot that Star was still just an exchange student. And that like every single exchange students the Diaz had ever hosted, she'd have to go back home eventually. And that simple fact was why he felt like he'd gotten the wind knocked out of him when Star's parents finally came to tell her that they'd be collecting her in one week to take her back to Mewni.

And just like that, losing Star became a terrifying reality instead of a distant nightmare that would never actually come to pass. He was suddenly struggling to breathe as he watched servants off the royal family casually pack every last shred of Star's existence into crates and chests, hauling them away through glowing portals to Star's homeland. It almost felt like he was getting jammed into a small box himself and every mouthful of air he took brought him spiraling towards suffocation. Every day that they drew closer to Star's departure was like watching numbers tick away on a bomb that would completely destroy the best thing to ever come into Marco's life, and there was nothing he could do to stop it.

Seven. Star announced that she'd be leaving to the whole class one day before lessons started, much to the dismay of the rest of Echo Creek. All day long, everywhere he went, that was all anybody talked about. Not to Marco, though. As soon as anyone noticed Marco in the room, they gave him a long, pitying look, like he had suddenly been diagnosed with a terminal illness. By the time school ended, Marco was desperate to hit something to relieve some tension.

Six. Queen Butterfly came by to personally thank the Diaz family for taking care of her daughter, and to oversee the servants she had sent to pack Star's things. She barely acknowledged the humans who had occupied the house alongside her daughter while doing so, except to take a few moments to 'express her gratitude' towards Marco for being such a good influence on her daughter, commenting that Star constantly spoke of him in their calls and crediting him with helping her realize that her recklessness was more often harmful then helpful. If Marco wasn't so intimidated by the woman (who seemed like the type who handed out death sentences on a daily basis) he would have told her exactly where to stick her gratitude.

Five. Their classmates threw a going away party for Star, which was hosted by Brittney Wong, of all people. Despite the cheerleader's best efforts, even she hadn't been immune to Star's strange charms forever, and Marco caught her half-threatening/half-begging Star to come back to earth and visit her. The party got a little bit crazy, as was the norm for all parties that Star attended, and the night ended with half of the party guests covered head to toe in chocolate pudding and the Wong family's swimming pool being launched into the moon. Marco half hoped that the Monarchs of Mewni would catch wind of the incident and decide to leave Star on Earth forever, but sadly that didn't end up being the case.

Four. Gifts arrive from the Butterfly family as thanks for hosting Star. Jewelry that was probably worth more than their whole house, a dozen treasure chests weighed down with gold coins, rare and delectable sweets from the other dimension, and even their own pet Manticore. After the Manticore tried to eat one of the Laser Puppies and got blasted in his eye for his trouble, Marco's parents quickly decided to send it to Mr. Diaz's cousins, who owned some farmland where the mythical beast could have the room to stretch it's legs. And wings. They kept the other gifts though, much to Marco's disappointment. He secretly hated to see them, and be reminded that the life that Star would be returning to had so much more to offer then any he'd ever be able to offer her if she stayed on Earth.

Three. Star began a day long quest to find new homes for her colorful array of pets, since her mother wouldn't allow her to bring them back to the castle with her. The Diaz's kept the Laser Puppies, but the rest of Star's bizarre magical zoo is too much for them. Janna took in the Giant Purple Moon-Cat that had nearly eaten Marco, and Jackie agreed to take care of the Beanbag Monster. Alfonzo accepted the weird talking poodle thing, and Brittney took most everything that was left, including the flying pig and all of the cute, itty-bitty friends that hadn't already been claimed by the other cheerleaders (or the football team, who liked that they were small enough to hide from their parents. Justin was especially fond of Prince Hissy).

Two. The Diaz family has their last family dinner with Star, showering her with their simple homemade gifts and hugging her every other minute, chocking back tears and telling her about how wonderful it had been to host her and how much they were going to miss her. It's obvious that it's killing Star a little at a time to think about separating herself from them, but Star just smiles through her tears and thanks them again before promising to come back and visit soon for the hundredth time. Marco just stares at his plate, mindlessly pushing his food around with a fork and trying to pretend that this is all just a really bad dream, and things will go back to normal soon.

One. Star's room had been returned to the way it was before the crazed magical princess came bursting into his life with glitter and fire and rainbows. A simple single bedroom, with only a twin bed and a bedside table. The bathroom similarly had been cleared of Star's epically impressive mess, leaving just Marco's things behind. No more magic mirrors, or deadly swords and morning-stars to trip over, or random dresses and high heels creeping over onto his half of the countertop, or stuffed toys hidden away in the medicine cabinets.

Marco never hated neatness more in his entire life.

Star was unnaturally quiet on that last day, which only made Marco more upset about the whole mess. Why didn't she scream and fling spells around and make it clear that under no circumstances whatsoever was she returning to Mewni? Why didn't she tell her parents 'thanks, but no thanks?' and explain that earth was her home now, and Mewni would just have to learn to get along without her? Or maybe cast some kind of time loop spell, so that the two of them could just spend forever with one another and never have to worry about the rest of the world, or growing up and being separated? Father Time would probably do that for them, right? He owed them for getting him off that wheel, after all.

It was selfish of him to think this way, and Marco knew it, but he just couldn't help it. Star was just that important to him, and he didn't want to lose her like this. Not even to her own kingdom.

"Guess this is it, huh?" Star asked him, forcing a smile as she stood in front of the portal that would take her home. She had already said goodbye to everyone else, but she had saved Marco for last and asked everyone else to leave so they could be alone. Marco wasn't sure if it was better or worse this way. "At least you don't have to worry about me getting us into trouble anymore right?"

But I want you to get us into trouble. Marco thought to himself. Even if I acted like it was a pain, I always liked it because it made life fun.

He didn't dare tell her that, though. Just stared at his tennis shoes and tried to remember how to breathe.

"I'll… I'll give you a call and stuff, okay? I mean, I think I got an old mirror around somewhere, so I can send it to you and we can still talk and stuff. And I'll leave you Ponyhead's scissors, so you can come and visit me. If you want. The guards'll know to send you right through, I promise."

He didn't want to 'call and talk' or 'come and visit.' He couldn't stand the thought of her being more then the next bedroom away from him, let alone in a completely different dimension. That kind of distance just wasn't acceptable. Not being able to see her every single day, no matter what the circumstances, wasn't acceptable.

"Anyways… I know I wasn't always the easiest person to live with and I am sorry for that, but before I go I just wanted to tell you that I'm really happy I got to meet you and be your friend Marco. You made me into a better person, and I… I just…" Star trailed off, tears beginning to spill over and track down her cheeks as her emotions got the best of her. Marco's own eyes went wide at the realization that Star was crying. That Star was crying because she had to say goodbye to him even though she didn't want to. Because that was the right thing to do.

Swiping furiously at her cheeks with her hand, Star gathered herself the best she could and jumped forward to pull Marco in for one last hug, squeezing tight and burying her face into his shoulder for just a second before letting him go and turning her back on him to head through the portal that would lead to their separation. But before she could leave, Marco sprang forward and grabbed her slender wrist to holding her in place. Star probably could've broken free if she really wanted to, but instead she turned her tear-streaked face back to him once more as desperation swelled within him. Forget doing the right thing. The right thing should never hurt as much as this did. Impulsively, Marco opened his mouth and let the words spill out, staring into Star's eyes as he futilely fought back tears of his own.

"I don't want you to go." He begged. "I want you to stay with me. Please, Star."

Star's eyes went wide at Marco's plea, so similar to the words he had spoken on her first day on earth after they had fought off Ludo as a team, before her tears began falling even more as her lips began to quiver. Twisting around to face Marco again, Star buried her face into his chest, her shoulders trembling as she tangled her fingers into his hoodie and began to cry with all her being. Automatically, Marco released his hold on her wrist to hug the blonde closer, as though afraid that she would evaporate if he let her go.

Later on, he'd lie awake in shock, wondering at just how it had happened, but at the time he wasn't thinking at all. He was far too busy feeling to ever give thinking a second thought. Feeling the way the amazing girl in his arms shook as she cried loudly into his chest. Feeling the grief finally overwhelmed him and brought him to his knees, Star falling to the floor with him as he went down. Feeling the tears that flowed down his own face as touched his forehead against hers and held her even tighter. Feeling himself look at her, with her eyes red and puffy and snot dripping from her nose as she babbled incoherently about how much she was going to miss him and how much leaving hurt between sobs that made it difficult for her to breathe, let alone talk. Feeling his heart break at the sight of her looking so defeated, and in so much pain.

Feeling his lips against salty, wet cheeks, kissing away tears as they fell.

And then, feeling himself kissing her fully, and her kissing him back just as fervently as an invisible puzzle piece fell into the place it was always meant to occupy and a sense of wholeness filled him to the brim, chasing away the grief and anxiety and frustration and everything else he'd been feeling to this point. Breaths intermingled as he and Star broke apart for the briefest of seconds for air before meeting each other's passion once more. Star's nails clawed at his neck as she tried to pull him in closer and eliminate the space between them. Marco's hands were probably leaving bruises on her waist as he held her, fingers sliding against the fine silk of her royal gown as he became entranced with the feeling of her ribcage rising and falling with every breath. Mewni, Earth… everything else seemed to disappear for Marco in that moment.

Everything except Star.

He wasn't sure how long they went on like that. It could have been anywhere from a few minutes to a solid week as far as he was aware. And it probably would have lasted far longer, if not for Marco's mother growing concerned at his continued absence and coming back up to knock on the door and check on her son.

"Marco? Sweetie? Is everything alright in there? Do you need me to come in?" Marco only heard her dimly at first, like someone was shouting at him from the other end of a large field. It took a moment for her words to sink in at first, but once they did Marco's heart nearly stopped as panic overrode all other senses and he pulled himself apart from Star to turn and shout at the door.

"NO!" He bellowed, lungs working overtime to try and make up for the air he'd lost during the intense make-out session he's just partaken in. "Don't come in!" The knocking stopped a few moments before his mother spoke again, startled and concerned, and yet also trusting in her son.

"Alright then. Just shout if you need me, okay?" Marco heaved a sigh of relief as he heard her feet pad away from the door, dragging a trembling hand through his hair as he turned back to Star only to falter the moment he saw her sitting dumbstruck on the floor, hands covering her mouth and eyes wide in disbelief. It was only then that the full scenario finally hit Marco all at once.

He kissed Star.

As in This-Is-My-Best-Friend-Star-Butterfly.

He had kissed his best friend. The crazy, but well-meaning magical princess from another dimension.

And suddenly, he wasn't quite sure what to do about that.

So instead of doing anything, he just sat there staring at her in shock as his actions-and all their implications- finally started to sink in, watching Star's face slowing begin to turn so red that her heartmarks were completely camouflaged by her blush.

Hand still clasped to her mouth, Star jumped to her feet and fled through the portal like someone had set her on fire. By the time it dawned on Marco that she was trying to escape, he was already too late to stop her from leaving. And yet he couldn't help trying anyways, lunging forward to try and grab her- her arm, her dress, anything really- to stop her from going through the portal and leaving him behind. But when he did, something hard and sharp dug into his leg, making him draw back with a shout of pain as the portal faded close behind the Princess as Marco sat confused and heartbroken in it's wake.

He had kissed Star.

And now Star was gone. Back to her own dimension so her parents could prepare her to become Queen.

And Marco had kissed her.

Why did I kiss her? The teen asked himself, despite already knowing that he didn't have a good answer to the question. 'Because I felt like it' wasn't a good reason to plant one on your best friend. No, scratch that; 'Because I felt like it' wasn't a good reason to plant one on anybody. Star was always the wild and impulsive one between the two of them, while Marco preferred to think things through carefully before he made any moves.

So what had driven him to change that now, of all times? Because Star was leaving? Was that really a good excuse to suddenly initiate a passionate make out session with your best friend?

Somehow, he kind of doubted it.

Groaning in frustrated confusion, Marco buried his face into his hands in dismay, drawing his legs closer to his chest as he did so until one of his feet struck something hard and sharp, the same object that had stopped him from catching Star before she could leave. Pulling his hands away, Marco looked down to see what the object was, gaping in disbelief at what he found.

Sitting innocently on the carpet by his foot was Star's tiara, it's gemstones glittering prettily in the sunlight. The symbol of Star's noble birthright and status as Princess had stopped him from trying to keep Star from leaving him.

The irony of the situation was too much to bear, and suddenly Marco was laughing and crying all at once.

Later that night, after Marco had changed and readied himself to go to sleep, he set Star's tiara on his nightstand before climbing in his bed, turning to gaze at it with tired eyes as he waited for his dreams to come. The golden headpiece seemed to glow in the moonlight, and seeing it sitting there made Marco feel just a little less empty.

He didn't know why he'd kissed her. He had no idea how he'd explain himself to Star the next time he saw her. But he would see her again, even if it wasn't as soon or as much as he wanted. And in the meantime, he could try and figure things out a little more, so that when he did see Star he knew exactly how he felt and would be able to tell her and they'd be able to move forward together.

And they would, Marco realized with a small smile as exhaustion overcame him and his breathing began to even out. It was a little silly of him to be afraid that not being able to see Star every minute of every day would erase the time they had spent with one another, how how important they were to one another. No matter what, Star was still his best friend. Even if they couldn't always be side by side, she would still be his best friend and no distance or kingdom or demon pretty boy could ever get between what they had. Nothing was going to change that.

Not even the slightly terrifying but all too likely probability that he might possibly have fallen in love with her without ever realizing it.