It's my headcanon that they're both Gryffindors for this. Fight me. ;)

Excited murmurs buzzed through the dungeon as the sixth years waited for their first lesson of the year to begin. It was well-known that Slughorn always started his N.E.W.T. classes with a demonstration of powerful potions that the students had yet to encounter, but he switched them up every year, so the incoming class never knew what they were about to see.

"What do you think he's going to show us?" Blaine whispered. "I'm hoping for Felix Felicis, personally."

"I've heard Slughorn's Veritaserum is so clear it's almost invisible," Kurt whispered back, leaning in close. They were huddled so tightly that Blaine could smell Kurt's hairspray and signature Gilderoy Lockhart cologne - the man may have been a scam artist extraordinaire, but his beauty products were still top-notch. Blaine himself used Lockhart's raspberry-freesia hair gel to control his frizzy curls. "Maybe he'll show us how he does it."

"Ooh, that would be-"

Blaine's quiet agreement was interrupted by Slughorn's loud, genial cry of "Good morning, class!"

"Good morning, Professor Slughorn."

"I know you're all wondering what special potion I have prepared for you today, so let's get right to it, shall we?" Slughorn said, smiling indulgently. He set down a covered cauldron on the center of his large desk, whipped off the cover, and asked, "Would anyone care to hazard a guess?"

Blaine couldn't quite see it from his place near the back of the room, but Rachel Berry practically flung herself out of her seat from the front row as she raised her hand.

"Amortentia, sir," she said when Slughorn called on her. "It's got the traditional mother-of-pearl glow and spiral steam."

"Ten points to Slytherin," Slughorn said, nodding in approval. "Now, I'm about to walk the cauldron past everyone so you can see the distinctive color and smell for yourselves. If anyone would care to share what aroma the potion takes for them afterwards, they will earn an extra point for their House."

"Oh my God, how lucky are we?" Blaine said in an undertone to Kurt. "I don't think he's done Amortentia since Harry Potter was in his class."

"I wonder what we'll smell," Kurt said, bouncing twice on the balls of his feet. He looked so cutely eager that Blaine wanted to - wanted to-

-what do I want to do right now? Blaine thought, suddenly confused. I didn't want to - he's my best friend, not my - but maybe -

Blaine's befuddled stream of consciousness was ended by Slughorn arriving at their table.

"Mr. Anderson," Slughorn said, lifting the cauldron up to Blaine, who leaned forward and sniffed.

"Mmm," Blaine hummed, instantly soothed by the presence of so many of his favorite aromas. He started listing them off in his head: new sheet music, warm baked goods, Kurt's aloe vera hairspray, Gilderoy Lockhart's bergamot cologne.

Wait.

Kurt's hairspray? Gilderoy Lockhart cologne?

He swiveled to the right as if commanded, staring at Kurt like he was seeing him properly for the first time. He recalled moments he'd thought nothing of - how he'd always thought Kurt was one of the most handsome boys he knew, the late nights cuddled up in the common room doing homework, the flutter of discomfort he'd felt when Head Boy Crawford asked Kurt to Hogsmeade last year - and finally understood his feelings for his best friend.

"Blaine?" Kurt whispered, concerned. "Why are you looking at me like that? What did you smell?"

"I, um," Blaine stuttered. "I think I smelled - you."

Kurt's breathing hitched as he got a look of overwhelming surprise on his face.

"Oh God, you don't think of me that way," Blaine said, panicking. "I just made our whole relationship weird and uncomfortable and now-"

"Blaine," Kurt said, placing a finger to Blaine's lips to stop him. "It's not weird. It's just - I smelled you, too."

Blaine felt an explosion of butterflies take over his stomach.

"I wasn't even surprised, honestly, I think I've been in love with you for ages now. I mean, I only just realized last year, but when I look back, I can't figure out how or when it started," Kurt continued. "It's just always been you."

"Even when you went out with Adam last year?" Blaine asked, hardly able to process what Kurt was saying.

"Especially then," Kurt said, eyes shining as he laughed. "We went to Madam Puddifoot's, and all I could think was 'This is so cheesy. Blaine would love it.'"

Blaine acted on instinct.

Heedless of his classmates telling Slughorn what they had smelled, he surged forward and kissed Kurt passionately, cupping Kurt's head in his hands to reassure him that this moment wasn't some magic-induced dream. Kurt spasmed against him for an instant, clearly startled, but he soon wrapped his own arms around Blaine's shoulders and began kissing him back, realigning everything in Blaine's world.

It took a couple of minutes for Slughorn's pointed coughs and stern repetitions of "Boys!" to break through Blaine's cloudy mindset, but he did eventually pull away from Kurt, blushing in embarrassment.

"I suppose we don't have to ask what the two of you smelled," Slughorn joked, visibly thrown off by the unexpected display of affection. "Would you boys perhaps like a moment in the corridor to gather yourselves?"

Blaine and Kurt both nodded silently, grabbing their things quickly before scuttling out the door.

"So, uh. That was new and exciting," Kurt said once they were alone.

"Would you like to go to Hogsmeade with me this weekend?" Blaine asked. He realized it wasn't exactly a response to Kurt's statement, but he also didn't want to waste another second of time not dating Kurt.

"Yeah. Yeah," Kurt said, nodding vigorously. "I'd love that."

"You can show me that cheesy tea room you visited," Blaine teased, feeling giddy after Kurt's acceptance. "See if I really do love it."

"It looks like Valentine's Day threw up in there," Kurt said, laughing. "You, Mr. Hopeless Romantic, will adore it."

"And you?" Blaine asked.

"I'll be happy to be anywhere with you."