I couldn't help but write this. I heard about the Sebastian-Kurt showdown (oh, Tumblr, you wonderful thing) and this just...happened. I've not seen the promos or anything (I kinda want it to be a surprise), so it's completely my imagination about where they meet etc.

A note, however: by writing this, I am not contributing to the Grant-bashing that has been going on. Yes, I don't particularly like the Sebastian who lives inside my head (and I will be a little disappointed if he's not exactly how I imagine him); but there's no excuse to go hatin' on the guy who plays him. He's an actor. AC-TOR. He's not his character, and he actually seems perfectly lovely.

OK, I'll stop preaching now. I've said my piece, and my conscience is satisfied. I'm sure it was none of you guys, anyway. Oh, and I disclaim what needs to be disclaimed.

Kurt hated him already. He'd only just met him, but he hated him. The way he was looking at Blaine...Kurt couldn't ever remember being this furious.

And this guy, this Sebastian or whatever his name was, couldn't even be bothered to flirt with Blaine subtly, or in private; no, he had to do it when Kurt, Blaine's boyfriend, was sitting right next to them!

The problem was, Kurt couldn't even be angry at Blaine for not telling this guy to back off, because it was quite clear that Blaine had absolutely no idea what was going on. He was completely oblivious, as per usual; and whilst he was flirting back, it was in the same way that he flirted with waitresses in restaurants and shop assistants at the mall: a charming smile, a few casual compliments - nothing serious. Blaine just had a thing about being liked.

No, what really got Kurt was the way Sebastian kept turning to face him, wearing an odd smile. It was almost feline, the sort of smirk that Santana wore when one of her bitchy plans went particularly well. It made Kurt want to fly at him and scratch his eyes out; and he was so angry that he barely registered how...well, how jealous he was. This wasn't him, but he didn't really care.

Kurt stood, laying a possessive hand on Blaine's shoulder. "Blaine, honey," he said, addressing his boyfriend but looking at Sebastian. And yes, he knew that the emphasis he placed on the last word was completely unnecessary. And no, he didn't care. "I think Nick wanted to talk to you. Something about his solo."

"Does he? I'd better go and find him then. You two have fun," Blaine said, dropping a quick kiss on Kurt's cheek.

Kurt smiled at him and squeezed his hand. "I love you," he said softly, "you know that, right?"

"Of course," Blaine said, brow furrowed. He sounded confused, and looked at Kurt worriedly. "I love you too." He stayed there for a moment, still looking at Kurt, until Kurt smiled more strongly; then he nodded once and walked out of the room in search of Nick, glancing over his shoulder one last time before he reached the doors.

Sebastian stood, planting himself in front of Kurt. "How...cute," he said, his lip curling.

Kurt pursed his lips, biting his tongue to keep himself in check. "I don't know what you mean."

"Well, not cute exactly, more...pathetic. And obvious. Blaine may not have noticed, but for the rest of us it was hard to miss how jealous you were. And then playing it so scared and needy like that...I have to say, that was impressive."

"Look, just back off, OK?" Kurt said. "He's my boyfriend. He chose me and he loves me, you heard him say so." He hated it, but he could hear the jealousy in his voice as he spoke.

Sebastian just raised his eyebrows. "Things can change," he said cryptically; and Kurt saw red. His hand shot up and he shook all over; but before he could do anything, Blaine burst back into the room, letting the door slam behind him.

"I couldn't find Ni - what's going on?"

"Nothing," Kurt said. "Let's go." He turned and walked quickly out of the room, leaving Blaine to shoot a puzzled glance at Sebastian, who was grinning smugly, and dash down the hall after Kurt.

"Kurt! Kurt, wait!"

Kurt was already halfway down the street by his car when Blaine caught up with him. He ignored Blaine's calls and climbed into the driver's seat, starting the engine. Blaine quickly climbed in the other side and pulled Kurt's off of the steering wheel, capturing his wrists.

"Kurt, what is it? What's the matter?"

"Nothing," Kurt said, sounding agitated. "Nothing's the matter."

"But you...you looked like you were going to hit him, Kurt! I know you, and you'd never..."

At that, Kurt snapped. "Don't you see?" he said, his voice rising rapidly. "Didn't you notice that he was hitting on you? Or the snide looks he kept giving me, as if to say, 'Ha ha, I'm much better looking than you and your boyfriend's going to leave you for me'?" He stopped and swallowed hard, calming himself before continuing quietly: "And why wouldn't you? Who would choose me over him?"

Blaine was quiet for a moment, and his silence seemed to confirm all of Kurt's worst fears. He wrenched his hand from Blaine's grip and turned to climb out of the car, to just get away; and he was halfway out of the door when Blaine said, "I would," his voice low and intent. Kurt turned quickly, doubt sketched across his face.

"All this, it was just because you were jealous?" Blaine asked. "Why? You know I love you."

Kurt nodded reluctantly, his eyes on the floor.

"Hey," Blaine said, nudging his finger under Kurt's chin and coaxing his head up. "I love you. I. Love. You," he murmured, punctuating each word with a kiss. He held Kurt close to his side, and Kurt rested his head on Blaine's shoulder, nuzzling into his neck.

"You said he was hitting on me - I didn't even notice," Blaine said. "I wasn't flirting with him, was I? I'm so sorry, Kurt, I-"

"Shut up," Kurt advised, pressing his lips against Blaine's neck. "You flirted with him in exactly the same way that you flirt with everyone." Blaine's eyes widened and he opened his mouth, probably to start apologising again, but Kurt just laughed. "Don't worry about it. I don't blame you: the way you flirt with the rest of the world is not the same way that you flirt with me."

"That's good, right?"

"Yes, it's good. It means you're mine and no one else's."

Kurt shifted round, moving so that he was sat in Blaine's lap, facing him.

"Did you have to move?" Blaine asked. "I was enjoying that."

"The handbrake was digging into my ribs," Kurt replied dryly. "Besides, I guess I can make this quite enjoyable for you too."

He curled his arms around Blaine's neck, tangling his fingers in the loose curls there - he'd finally persuaded Blaine to ditch the gel, for one night at least - and pressed one quick kiss against his collarbone, teasing him. He breathed lightly on Blaine's ear, making him squirm beneath him; before Blaine pulled Kurt's lips to his own, kissing him fiercely. But Kurt quickly broke the kiss, trailing his mouth along Blaine's jaw. he sucked gently at the skin of his neck as Blaine traced his fingers across Kurt's back and stomach , quaking under his ministrations. Kurt smiled at Blaine's reaction and sat back, admiring his handiwork. He ghosted his thumb across the mark he'd left on Blaine's collarbone, the red circle that would soon enough become a deep, dark-coloured bruise, and whispered, "There. You're mine."

And Sebastian - not to mention everyone else - had better not forget it.