Last time I was stateside I was only 18 and therefore didn't bother going to Vegas. Sounds like a fun town though, the kind of place I could see Chuck enjoying, and Blair loathing. Unless of course she had Chuck properly by her side, in which case I think she would be happy anywhere. So this is just a little one-shot about the repercussions of the drunken exploits of Chuck and Blair on a visit to Vegas. What might he convince her to do while intoxicated by champagne and his recent admission of love?

Serena checked her phone again for missed calls or text messages from either Chuck or Blair. While it was not unusual for Chuck to suddenly vanish destination unknown, Blair's super-organised and somewhat anal streak had never let her go anywhere without informing her best friend of her full itinerary. Even in her darkest days, after she had been refused acceptance to Yale, Blair had always at least let Dorota know where she was going to be. Serena cursed the effect that her stepbrother had on her best friend. It was obvious that he was doing something to keep her...distracted. 'Come on Blair,' Serena thought, 'you can at least stop the lovemaking for a few minutes to return any one of my 55 missed messages.' Eeew, she didn't want to be thinking about Chuck and Blair in bed! It was bad enough that Blair had never shown any compunction about discussing what a fantastic lover he was. Before, Serena had always thought that Chuck's lothario reputation rested solely on his ability to attract numerous girls to his bed through his money and status, rather than performance or technique. But Blair had assured her, much to her horror, that that was not the case.

Now it had been three days since Chuck and Blair disappeared shortly after the drama that was graduation. The mayhem of that day had started when the entire school received a gossip girl blast during the ceremony relating how Blair had slept with Chuck's Uncle Jack the previous New Year's Eve. For Serena this attempt to humiliate Blair on what should have been a day of triumph and sentimental nostalgia was the final straw in her increasing disillusionment with the world of gossip girl. Serena knew she wasn't in Blair's league, but she considered herself more than capable of taking the anonymous blogging bitch down. (As it turned out, she had been wrong, although she had managed to get even with Georgina for sending in the post in the first place).

Serena had been all the more set on wreaking revenge on Gossip Girl because she couldn't help but feel guilty about the whole Blair/Jack situation. If she had been in New York on New Year's than Blair would never have been so lonely or so drunk that she was willing to hook up with Jack Bass in order to gain some comfort and release. But while Blair had been getting taken advantage of by that manipulative bastard, Serena had been living it up in Brazil, oblivious to the selfishness of sunning herself while the rest of her family and friends dealt with the fallout and misery caused by her stepfather's death.

Serena felt doubly guilty because she was sure the blast would be yet another roadblock in the path of a real Chuck and Blair relationship. Serena had had her doubts about Chuck in the past, hadn't really been able to see what Blair saw in him. He could be useful, yes, when handling incidents like that pool party or Georgina's return, but he was also a sleaze who preyed on girls and broke her best friend's heart. She had told Chuck to fight for her, because she thought that is what Blair would want her to say, but she was relieved when it seemed like Blair was making the safe choice with Nate. Not until prom, when Chuck had gone out of his way to make sure Blair had the perfect evening, even if he wasn't the one by her side, had Serena realised that Chuck also had a heart that could be broken, a heart that seemed entirely devoted to her small, whiny, catty best friend.

Serena thought that there must be something intoxicating about having someone in love with you who had never really loved, really felt, anything for anyone else before. To be the sole object of their affections. Sure Dan had been romantic and devoted to her, but she knew that before her he had at least thought that he was in love with Vanessa, and had known that he was capable of feelings for persons other than her. Plus he had a whole, tight-knit family to love. Similarly, anyone who went out with Nate would have to know that he had frequently been in love with other girls before, and put up with the possibility that he might again be distracted, if not by his family or friendship dramas, than by another, suddenly more interesting woman. But at prom Serena suddenly understood that not only did Chuck really love Blair, but that she was the only person for whom he had ever properly experienced that emotion. It was a compelling thought, one that had converted her into a Chair supporter.

So when the blast had come through about Jack Serena had felt a sickening dread in her stomach, fearful that this would once again turn Chuck's attitude towards Blair to one of bitter hatefulness. Seeing the crushed look on Blair's face and her reluctance to meet Chuck's eyes, she was certain that Blair had been afraid of the same thing. Chuck's reaction had therefore come as a complete shock. Rather than sarcasm or accusations, he had jumped to Blair's defence when Hazel and Penelope made some catty comments about her addiction to all things Bass, quickly cutting down her minions with some knowing retorts about the things they had got up to at past New Years' events. When he and Serena had been left alone he admitted that he had known that Jack and Blair had slept together for a while, Jack having used it as a final jab after taking the company from him. But, like Serena, he apparently blamed himself for the incident, admitting to her that he knew Blair would never have had anything to do with Jack if she hadn't been depressed over him rejecting her love and then disappearing from her life. Besides, he hardly felt in a position to judge Blair over a single sexual indiscretion when he had womanised the world over and repeatedly flaunted his conquests in front of her even after her heartfelt declaration.

So, if anything, the incident had seemed to bring them closer together, had enabled Blair to clearly see that Chuck really did love her and would accept her just as she was. They had been able to start with a clean slate. It was thus not totally surprising that they seemed to have run off together. Serena supposed that they had things to talk over, time to make up for. They were probably far too blissed out to bother with such mundane things as calling their family and friends to let them know where they were and how they were doing. But Serena was glad because she knew Blair would finally be happy now....

"I hate him, Serena! He's a lying, manipulative Basshole!" Blair cried, tears streaming down her face as she burst through her best friend's bedroom door, interrupting her reverie.

Okay, so she wasn't happy. Serena had been wrong before.

"Oh, B, what happened? I thought you two had gone away somewhere to make up," Serena put her arms around her best friend as she collapsed beside her on the bed.

Blair sniffled. "We did. But it was all part of one of his twisted, evil schemes. He's the same conniving motherchucker he always was!"

Serena's heart plummeted. Chuck must have only pretended concern for Blair over the whole Jack thing to make her believe that he really cared about her so that it would be all the more gut-wrenching when he told her he wanted nothing to do with her. It was the kind of stupid, calculatingly cruel thing that Chuck would do out of jealous resentment. Everyone knew to beware of a Chuck Bass scorned. Serena rubbed her friend's shoulder soothingly. She had to get all the details, let Blair talk it out, before she devised the method by which to murder her stepbrother.

"Did he end things with you? Take back his 'I love you'?" Serena tried to confirm through Blair's hiccoughing sobs.

"No," Blair blubbered. "But how can he say he loves me and then do something so horrible? He's a basstard."

One detail at a time, Serena thought. "Where did he take you?"

"Vegas," Blair huffed. "I should have realised he'd never change when he insisted on taking me to such a tacky, hedonistic, exhibitionist town. But we were so happy, I didn't care." The last word was drawn out in a particularly long wail.

Serena's mind instantly went to images of Blair walking in on Chuck making out with a chorus line of Vegas showgirls. "So he took you to Vegas. What did you do then?"

"We just hung out at first. We didn't really leave the hotel suite the first two days," Blair reddened, leaving Serena in no doubt as to how they initially occupied their time. "Then yesterday afternoon he said he wanted to take me for a big evening out. He bought me a beautiful new dress and asked me to wear my Erikson Beamon necklace. He took me to dinner and a show and I thought it was all so romantic. But he kept plying me with champagne. Then we went out to see the sights, clubbing and gambling, and I didn't realise how many cocktails he was ordering for me. I was drunk, but I still can't believe he could have convinced me to do something so stupid..."

Blair broke off, her body racked with coughing sobs again. For a moment Serena's brow furrowed as she tried to make sense of Blair's ramblings, then cleared with dawning comprehension. After all, hadn't she herself made (or nearly made) the same mistake when she was away, alone with a boy she liked and very drunk? What drunken mistake was Vegas famous for producing? Chuck obviously hadn't taken Blair there by accident. He had engineered the entire situation so that she would marry him without him having to go through the fear of possible rejection an actual proposal would cause or the rigmarole a New York society wedding would necessarily encompass. Of course, for a girl like Blair, who had dreamt of the perfect wedding since she first understood what the word meant, a quickie ceremony in Vegas would be simply unacceptable. No wonder she was distraught. But maybe Serena could get her to look on the bright side. At least now she wouldn't have to worry about how committed to their relationship Chuck was.

"There, there B," Serena soothed. "It will all be okay. I know this may not be precisely how you wanted things to be but it is Chuck after all. You do love him, right?"

Blair drew herself up and glared balefully at Serena. "Whatever feelings I might have for Chuck are beside the point. I don't want this, I've never wanted this. The whole thing is a terrible mistake."

Serena felt bad for her best friend. But if she was adamant that the marriage was a mistake, there was an obvious remedy to the situation. "Hey, Blair, I know it may be bad and you might be worried about what people will think. But these things can be undone. Maybe no one else will even ever have to know."

Blair sighed. "I know it can be undone. But I'll always be scarred. I'll never be blemish free."

Serena understood what Blair meant. When she had thought that she was married to Gabriel and would have to divorce him, it had been a little mortifying to think she would be a divorcee at eighteen. But at least she had known that it was the kind of behaviour that wasn't completely unexpected of her, given both her own past and her mother's marital history. But B had always been adamant that when she settled down it would not only be the perfect wedding, but the perfect marriage. Which meant it could only happen once. A divorce did not fit in with Blair Waldorf's image of perfection.

"I get it B. But hey, maybe you don't have to get a divorce. Maybe you have grounds for an annulment. That would mean this marriage wouldn't count, not even in the eyes of the church."

Blair stared blankly at her friend. "Serena, what are you talking about? What marriage?"

Serena looked confused. "You married Chuck in Vegas, right?"

Blair gaped at Serena for several more seconds, then burst into a fit of hysterical giggling. "Oh Serena, like I could ever be drunk enough for that! I'm not you!" Blair continued laughing.

Serena frowned, stung by her friend's derision and her own obvious failure to grasp the situation. "So what was this horrible mistake you made then?"

Blair sobered instantly. "You're right, I shouldn't laugh," she said. "My own error in judgement is almost as equally egregious and, in its own way, permanent. Serena, prepare yourself."

With that, Blair turned around so that her back was facing her best friend. She reached behind herself to pull up her top and pull down her skirt slightly, so that Serena could just see the top of the right cheek of Blair's bottom.

Now it was Serena's turn to start laughing. Part of her knew it wasn't funny, could understand her friend's anger and humiliation, but the other part just couldn't get over the hilarity of the situation. Because there, on Blair's lower back, in very tiny but nevertheless perfectly clear writing, was a tattoo that read 'Property of Chuck Bass'.

Blair pulled her top back down and turned on her friend in anger. "Serena, how can you find this amusing," Blair hissed. "I cannot have a tattoo. I especially cannot have this particular tattoo. Who the hell does that Basshole think he is, referring to me as his property?"

"Oh B, I know all that," Serena said, trying to stop the laughter that had actually made tears begin to stream down her face. "But, oh my god, it's just so funny. Something like this could only happen between the two of you. Only the two of you are so insecure you need to manipulate and torment each other into facing your feelings this way. Only you two actually enjoy this brand of torture." Serena couldn't help but continue to chuckle.

"Enjoy it! Ha! I'm mortified. And we'll see how much Chuck enjoys it when I set out to prove that nobody owns me."

Serena continued to snigger.

"Fine!" Blair raged. "Laugh it up! He certainly thought it was a fine joke too!"

A darkly handsome form filled the doorway. "I never said it was a joke Blair, although I'm not unsympathetic to my sister's amusement," Chuck drawled in his husky tones.

"Welcome back, oh brother mine," Serena smiled at Chuck with a look that unmistakeably said 'while I find your antics humorous, I won't stop her if she decides to kill you'. "I hear you've had a busy trip."

"It was not uneventful," Chuck returned Serena's smile with a smirk that said 'I can charm my way out of anything, especially when it comes to a certain best friend of yours'. Then he turned and re-directed his attention at his petite and dangerously enraged girlfriend. He smiled at her winningly. She scowled at him menacingly.

"If it wasn't a joke, then what was the big idea Bass? Or do you still have a death-wish? Were you hoping this time around I'd actually help by pushing you off the roof? Because at this point I'm more than happy to oblige," Blair spat at her lover and sparring partner.

"Of course not. Now that I have you I have all the reason a man needs to live," Chuck employed the low, seductive tones that made Blair's body shudder. But when he spoke again, there was a defensive edge to his voice. "However, I thought a little reminder to the rest of the world that I do indeed have you might not go astray."

He was the epitome of arrogance. Serena had always associated Chuck with egotism and conceit (who else would think the phrase 'I'm Chuck Bass' was a legitimate rejoinder to almost any criticism or question), but this was something else. Blair was going to explode any second. She decided to jump in first.

"But Chuck, you went off at Nate for trying to mark Blair as his territory. What you've done is even more extreme. Slightly psychopathic even. I know you're new to this whole relationship thing but you have to realise any good relationship is built on trust. You have to trust Blair and not indulge this primitive need to stake your claim on her," Serena reasoned.

"Thanks for the relationship advice, sis. Of course, it might mean more from someone who's last boyfriend didn't turn out to be a lying con artist. But you'll be pleased to know that I agree that a good relationship is built on trust. And I do trust Blair," Chuck smiled. "And I hope she knows she can trust me. But there are millions of men in the world who are not part of this relationship and who I emphatically do not trust. The tattoo is for their benefit. Only fair to let them know, seeing as I tend to be kind of harsh to people who touch my things."

That seemed to be the final trigger in initiating a full-blown Blair Waldorf meltdown. She grabbed Chuck's lapels and roughly pulled him down to her eye level. "Listen to me Charles Bass, and listen good," she declared. "I AM NOT YOUR PROPERTY." She enunciated every word clearly and precisely.

"That's not what your back says," Chuck grinned back, bringing his lips dangerously close to Blair's in an almost kiss. "And I must say, it's kind of a turn-on." Serena had never witnessed their strange love-hate dynamic so clearly. They were locked in a bitter confrontation, but with their faces mere millimetres away from each other, it felt like any second the rage could erupt into a different kind of passionate display. The sexual tension was palpable.

The moment was broken by Blair swiftly kicking Chuck's shin with her pointy Jimmy Choos in one of her deadly signature moves. Even that did not wipe the smirk off Chuck's face. But Blair's next words as she stormed out did.

"Well, I guess I'm just going to have to prove you, and it, wrong. Blair Waldorf doesn't belong to anyone. I thought you would have learnt that by now?" Her sugary sweet tone was diabolical.

Chuck's face grew creased with worry as he stared at the doorway through which she'd disappeared, contemplating Blair's words. He dropped onto the bed next to Serena.

"How long do you think before she cools off?" he asked.

Serena rolled her eyes. "I don't know, she is a master when it comes to holding a grudge. And it was a pretty rotten thing to do Chuck. You know how Blair feels about tattoos. Especially ones with people's names. I think she once said that they were more vulgar than those hats you can get to drink beer out of. It wasn't exactly great thinking on your part to get her drunk and force her to get one."

Chuck's face and voice turned hostile. "Hey, it wasn't like I planned it. I was really drunk by that point too. It all just seemed to happen."

Serena sighed in relief. "Well, you should tell her that. Because right now I think she thinks you got her drunk on purpose in order to trick her into getting it."

"Please. If the whole thing had been that carefully thought out I would have known better than to get one myself. But we were both drunk and somehow tattoos were mentioned and it seemed like a good idea at the time."

Serena gaped at her stepbrother. "You got a tattoo too?"

"Of course," Chuck sighed as if frustrated by the limited mental workings of a very small child. "Tit for tat."

Serena started giggling again. "You mean you have a tattoo on your butt that says 'property of Blair Waldorf'." Again, she couldn't control the laughter.

"Not exactly," said Chuck, his expression shifty.

"Then what does it say?" Serena enquired. Chuck did not respond.

"If you don't tell me, I'll just find out from Blair," Serena prodded.

"All right, I'll show you, but this goes to the grave Serena. If I get any grief from bumbling Brooklyn I will come after you," Chuck said, beginning to remove his shirt.

Serena yelped. "Okay fine, I won't tell anyone. But you don't have to show me, Chuck, I don't want to see your butt."

"Relax, sis, it's not on my ass," Chuck said rather haughtily as he bared his right shoulder.

Serena couldn't believe her eyes. Chuck's tattoo was much bigger than Blair's and much more intricate, comprising both a picture and writing underneath. She leaned in to take a closer look.

"A butterfly, Chuck? Not very manly," Serena gibed.

He glared at her. "Butterflies happen to have a special meaning in our relationship."

Serena raised her eyebrows sceptically.

"On the night of her seventeenth birthday, Blair asked me if I liked her. I told her that since we'd been together I hadn't been able to sleep or eat. That there was something in my stomach, fluttering. She said I had butterflies."

Serena's eyes glistened. The way they went about things might be unconventional, and Chuck Bass wasn't the guy she envisioned her best friend ending up with, but there was no denying the romance of their relationship. "What does the writing say?"

"It says 'only for Blair'," Chuck answered quietly. "Because she's the only girl who's ever given me butterflies. And I'm pretty sure she's the only woman who ever will."

Serena's heart melted. She would help Chuck win Blair back. If he gave that speech again, Serena didn't think it would be too hard. And really, they were inevitable. Although she was thankful that the two hadn't ended up making the mistake of a quickie wedding on a drunken night in Vegas, she didn't doubt they would end up married one day.

Serena smiled at Chuck. "You know, when Blair told me she had made a terrible mistake when she was with you in Vegas, I was afraid you two had got hitched. But now I think she could do a lot worse, Chuck. Who would have known that Chuck Bass was a romantic?"

"Glad to hear you feel that way, sis. Does this mean you'll consider standing next to your sister-in-law and possibly restraining her when I tell her that, after we got the tattoos, we actually did go on to get married in the Elvis chapel?" Chuck smirked, awaiting Serena's reaction in amused anticipation.

She appeared to have become catatonic so he continued. "I did get her drunk, but not in order to have her get a tattoo. I wanted to be married to Blair. I hate the term boyfriend. Husband sounds so much more appropriate, classy and mature." His smirk only grew as Serena's face became a war of emotions.

"WHAT?! You really did get married! She's going to kill you! I'm going to help her! How could you do this to her? To me? I was supposed to be her maid of honour!" Serena's voice was off the Richter scale, and she started slapping Chuck hard around the arms and shoulders.

He put his hands up to try and defend himself. "As my brilliant plan was part of a flash of genius that only occurred to me three days ago, I may not have fully hammered out all the details, like thinking to invite you or any other guests."

"It's no excuse, Chuck."

Chuck's face softened, his voice grew serious. "I love her, Serena. I just wanted to make it so that I'd be able to keep her forever."

Serena sighed. All the maturity and rationality of a spoilt little boy. But there was something sweet and endearing there too.

Well, a Vegas wedding might not be what Blair expected when she was little, but then not much had turned out the way she expected since Chuck Bass had taken over her love life. Things might not have been perfect between the two, but they somehow seemed right, Serena thought.

And for once, Serena had assessed the situation entirely correctly. Because although Blair shrieked and inflicted a few choice scars on Chuck's back when he informed her of their nuptials, it was not long before she decided that she quite liked the way it felt when he called her Mrs Bass. And Chuck did get to keep her, forever.