A/N: ikurtstanthings on tumblr posted that she wanted a fic where Kurt leaves Blaine at the altar and the only explanation that he gets is a list of pros and cons handed to him by Sam with a hundred reasons listed in the con column. I couldn't find the original post, so here's what I wrote. It's not lol, but I hope you all like it. (Warning for mention of Blaine and Klaine.)

Kurt lifted his head away from the toilet, where he had spent the last twenty minutes losing his breakfast, lunch, and dinner. 'How cliché was this?' he thought bitterly, flushing the toilet and struggling to get to his feet. Trapped in his hotel room, exactly one an hour before the big 'I do', and Kurt was sicker than he had ever been in his life.

But he didn't have cold feet. He had a complete and debilitating case of claustrophobia.

It wasn't his room. The Anderson's had sprung for one of the grandest suites at this hotel. It was his life closing in on him, strangling him, starting from the day on the Dalton staircase when he had accepted Blaine's proposal and getting tighter by the second ever since.

Kurt could settle. He could go through with it and hope that things got better. Isn't that what everyone always said? It gets better? He loved Blaine once. He could learn to love him again.

That might actually work, if it weren't for Sebastian.

Sebastian who watched, heartbroken, while Blaine proposed and Kurt said yes.

Sebastian who quietly pined for Kurt from afar for the last five years.

Sebastian who hunted Kurt down months before the wedding and laid out all his feelings, pledged his love for Kurt, a love that despite how hard he tried, how much he drank, how many men he fucked, he just couldn't seem to shake.

Sebastian who Kurt couldn't stop thinking of from that day on.

They met in secret, dined in private, got to know one another all over again. They drank coffee in out of the way places in the city, chanced the occasional movie, and a few times even went dancing.

As time went by Kurt realized that all of those things he missed in Blaine, all of those things he always thought Blaine could be again, already existed in Sebastian.

But Kurt was caged, committed. He had made a promise that he felt wasn't so easy to break. Plans had been made, set into motion, and Kurt couldn't call it all off now…could he?

It was a question he still hadn't answered and last night, while Blaine went out with Sam and Artie, presumably to some strip club that Kurt wasn't told about, Sebastian came to Kurt's suite, imploring him one final time to break it off with Blaine.

"But…but you don't even think you love him!" Sebastian had screamed, grabbing at his own hair in frustration.

"I…don't know what I want," Kurt admitted, his eyes red from crying, his voice barely audible from arguing with Sebastian for over an hour. "I'm confused."

"Okay," Sebastian, stopped his endless pacing and dropped to his knees in front of Kurt where he sat on the edge of the king-sized bed, "okay, don't focus on what you want. What about what you need?"

Kurt looked into Sebastian's face, green eyes imploring him to see reason not before it was too late. He was speechless. His lips moved, trying to explain, but he couldn't figure out where to start.

"Kurt?" Sebastian whispered, his voice heavy with desperation. "I love you and you love me. Isn't that all that we need?"

Kurt couldn't answer. Tears fell in earnest down his cheeks, but he simply shook his head, at a complete loss for words, any words.

Sebastian sighed. He felt drained. He pulled an envelope out of his pocket and laid it on the bed beside Kurt.

"I can't stay in the city without you," he confessed softly. "Knowing that you and Blaine are together, as husbands, I just…I just can't." Sebastian took Kurt's hands and held them along with Kurt's eyes. "But if you want to come with me…" He nodded to the envelope on the bed. "That's a train ticket. My train leaves at noon. And I hope…"

Sebastian couldn't finish. He kissed Kurt's knuckles, closing his eyes for a moment to breathe him in, and then rose to his feet and left without looking back.

Kurt wanted to follow. He wanted to chase after him and beg him not to go, but he couldn't. He couldn't make himself move. He couldn't make himself do anything but feel, and his feelings were crushing him from the inside.

Kurt collapsed on the bed beside the ticket and cried; loud, ugly sobs that shook his whole body, shook the bed beneath him, leaving him tired and gasping for breath.

At some point he got up to get a tissue. He walked to the vanity on the opposite side of the room and caught a glimpse of his wrecked face in the mirror. He grimaced. He looked awful.

He sat on the small covered stool in front of him and opened the vanity drawer, searching through his moisturizers and exfoliators for a packet of tissues. He found one supplied by the hotel, and underneath it was a stationary set consisting of a notepad and a pen. Kurt took them out and set them on the vanity. He blew his nose indignantly, staring thoughtfully at the blank page.

Kurt glanced at his watch, sitting on the vanity with the face clearly visible. It was ten o'clock. He had twelve hours until I do, and before then he vowed he would sort out his feelings. He would write them down, get them out, and then be done with them. He decided to write a list, like his mother had taught him. He would start with the pros and cons of marrying Blaine, and then the pros and cons of leaving with Sebastian, and whoever's list of pros were longer…well, he would cross that bridge when he came to it.

Kurt started with Blaine, folding the paper in half and dividing it into two equal sides. On the top, in big block letters, he wrote 'BLAINE'. Beneath that, he titled the columns 'PROS' and 'CONS'.

Starting was easier than he thought, though admittedly he started with the 'con' side first, since those reasons seemed to leap quickly to mind. He wrote and wrote, tears starting and stopping every now and then. He felt schizophrenic after a while. He would remember something blithe, something beautiful, and smile, but then immediately he would think of something heartbreaking and vile, and break into tears. He wrote until the cheap, free pen ran out of ink, and he had to go to his luggage to get one of his own. He finished the list, lying on the bedspread of his bed, where he fell asleep with one arm tucked beneath his head and the list clutched firmly in his hand.

Kurt rose from the bathroom floor and stumbled into his room. The first thing he saw was his tuxedo waiting for him. He walked up to it, ran his fingertips down the lapels of the Armani tux, and sighed.

'What a beautifully made straightjacket,' he thought grimly.

His eyes drifted to the vanity and the tear stained, crumpled list of 'pros' and 'cons'. With only thirty minutes left, he had a life-changing choice to make.

He only hoped he was making the right one.

Blaine fidgeted nervously with the cuffs of his tuxedo, surreptitiously peeking at his watch, trying not to show on his face how worried he was. His eyes swept the rows of guests, all staring at him expectantly, ready to share in what should be one of the happiest days of his life, all aware that the groom was already fifteen minutes late.

Kurt hadn't been quite the same ever since Sebastian dropped in out of the blue to visit so many months ago. Blaine wondered if Kurt was still upset about everything that had happened between them in high school, probably anxious that Sebastian's moving to the city meant another assault on their relationship, but Blaine had assured Kurt time and time again that he didn't want Sebastian or Eli or Sam or anyone else.

He only had eyes for Kurt.

Blaine heard the opening chords of the wedding march playing on the organ – cheesy, he knew, but his mother had insisted – and his entire body relaxed. He turned along with the rest of the room to watch his soon-to-be-husband walk down the aisle, eager to get the first look at the gorgeous man he would be spending his life with.

But instead of the prince Blaine had expected, a red-faced Sam hurried down the aisle, straight for him, a blank expression on his face and a plain white envelope in his hand.

"What-?" Blaine muttered, confused, reaching out for the envelope that Sam was handing to him. It had his name written on it in Kurt's flowery handwriting.

Sam offered Blaine no explanation. He simply shook his head.

Blaine felt his entire body go cold. He tore open the envelope, ripping it nearly in half. He reached into the tear and pulled out a slip of paper, accompanied by something heavy falling to the floor with a thud. Sam bent over to pick up whatever had fallen while Blaine read the note.

Except it wasn't a note. It was a list. Pros and cons with his name written at the top. The pros column was almost blank but the cons went on and on to the other side of the page, the print becoming smaller as Kurt tried to squeeze more into the limited space, each offense numbered.

Kurt had stopped at one hundred.

In the margin, Kurt wrote a brief message.

Blaine –

I could have kept going, so now I have to go.

I'm sorry.

Kurt

Blaine looked the page over front and back again, shaking in his hands. He felt Sam nudge his shoulder and he looked up at his best friend with watery eyes. Sam held his hand out to him, palm faced up.

"I'm sorry, man," he said sympathetically.

In the center of his palm sat Kurt's engagementring.

Sebastian stared out the window at the passengers boarding the train, picking out people in the crowd and following their progression from the platform to the doors – a mother with her toddler son in tow, fumbling to fold a cumbersome looking stroller and stow it underneath the train; a stooped-over elderly woman, about fifty years older than God, bidding farewell to her family gathered around her, some weeping, probably wondering if this would be the last time they saw each other again; a woman in a Naval uniform with a duffle at her feet, kissing her crying girlfriend good-bye.

There were no familiar faces there to see him off, though. No one crying at his departure.

No one who cared to say good-bye.

Sebastian started rummaging through his satchel, looking for his Kindle, hoping to while away the hours with his newly downloaded copy of Updike, when he heard someone take the seat beside him. He groaned quietly, but didn't look up. He knew the train would most likely be crowded, but he had hoped he might luck out and get away with sitting beside an unoccupied seat.

"Well, excuse me," an amused voice scolded him, "if you really want to sit by yourself, I can find another seat."

Sebastian rolled his eyes, about to make a snide remark, but it lodged in his throat.

He knew that voice.

It triggered something in his brain that sent messages all throughout his body.

That message – his life was about to become a thousand times better.

"You came," Sebastian said, raising his gaze from the contents of his bag to meet the smiling eyes of the man sitting beside him, backpack clutched in his lap, pinching his lower lip between his teeth.

"Yup," Kurt said with a single nod. "I came."

"But…but what about Blaine?" Sebastian sputtered.

"If I remember correctly, he wasn't invited."

Sebastian dropped his bag to the floor and grabbed Kurt's coat, pulling him into his arms, holding him tight to make sure he wasn't an illusion.

"I hoped, but never thought you would actually come," Sebastian whispered into Kurt's neck, squeezing his eyes shut.

"Do you still love me?" Kurt asked. He knew the answer, but he liked to hear it.

"Of course, I do," Sebastian said. "You know I do."

"Good," Kurt said, sighing. A sharp whistle sounded, warning the people on the platform to step back away from the train. It lurched forward, and with a few slow chugs, they started to roll away. Kurt tried to pull away to look into Sebastian's eyes, but Sebastian wouldn't let him go. Kurt chuckled and melted further into his arms. "I do love you, and that's all I really need."