Kurt began to notice Blaine's, uh, fetish not long after they started dating. They had rushed to Blaine's dorm room after class to take advantage of the few hours before his roommate got back from lacrosse practice, lips pressed together before the door was even fully shut behind them and bags carelessly slung to the floor.

Kurt's back was pressed to the door, his fingers twined with Blaine's where he pinned them near Kurt's head. The only sound in the room was their increasingly labored breathing and the slick slide of wet lips. As Kurt began to feel the need to come up for air, Blaine pulled away to trail his lips hotly along Kurt's jaw to the tender spot behind his ear.

Kurt let out a small squeak of surprise before relaxing into the door with a sigh. Blaine trailed his lips down his neck, featherlight, and god that felt good. He nipped at Kurt's collarbone and Kurt's hips snapped forward of their own volition.

His eyes flew open as he gasped, an apology on his lips, but Blaine didn't even seem to notice. He continued to suck gently at his pulse point, sliding his right hand out of Kurt's to tangle it in his tie and pull their bodies closer.

Kurt's head leaned back to give him better access as his fingers curled in Blaine's hair, ruffling the careful coating of gel. Blaine licked an unexpected stripe up Kurt's collarbone before blowing gently, and Kurt shuddered.

At that, Blaine finally pulled back to meet his eyes, pupil's blown and lids heavy, a dazed smile sliding lazily across his lips.

"That… that feels amazing," Kurt managed to stutter. Rather than answering, Blaine ducked his head and nipped at the sensitive spot where Kurt's shoulder met his neck, pulling aside his shirt collar as his fingers trailed down Kurt's side to wrap securely around his hip.

When Kurt stumbled back to his room several hours later, he looked in the mirror to see at least three red marks blossoming across his neck. I'm going to be wearing a scarf for a week. Somehow, he couldn't quite bring himself to care.

XXXXXXX

It became even more obvious as time wore on. Blaine would wrap his arms around Kurt's shoulders as he sat leaning over his homework, breath warm on his ear before he nipped at his earlobe and quickly trailed his teeth down the slope of Kurt's neck, causing Kurt to whimper appreciatively. Or, when going in for a quick hug between classes, Blaine would nose at his jaw before subtly pressing his lips to that one damn spot above his collarbone that made Kurt's knees go weak and his head spin. It had taken Blaine exactly five days of dating before he found that particular "on" switch.

Really, this was getting out of hand, but Kurt couldn't quite bring himself to protest until that week. Blaine had always been a cuddler — and Kurt was too, if he was being honest with himself — but the first week after they had sex was a whole new level. They couldn't quite manage to stop touching — a trail of fingertips across a knee, a hand on the small of the back, a rough kiss with tongues tangling at every opportunity, and most of all the neck.

Blaine would lean his head against Kurt's shoulder before Glee practice or during lunch and brush his lips across Kurt's collarbone whenever he thought no one was looking, while Kurt's breath hitched and he tried not to squirm in his seat. He would grab Kurt's hand and tug him abruptly into an empty classroom as they walked down the hall, pinning him to the wall and pressing their lips together roughly, biting and sucking at Kurt's lower lip before sucking under his jaw hard enough to bruise. Kurt's toes would curl and his eyes would nearly roll back in his head — partly from the sensation and partly from the knowledge of just how much this turned Blaine on. When their hips brushed, he could feel Blaine's erection straining against the tight fabric of his neon pants.

"Blaine," Kurt barely gasped out, pushing weakly at Blaine's shoulders. When Blaine pulled back, his eyes were unfocused. "We're in school, sweetie."

"So," Blaine murmured, his voice low and rough, the way it had been in Blaine's bed last week. Kurt's cheeks flushed. When he didn't respond, Blaine ducked his head again, clearly aiming for Kurt's neck, but Kurt held him back.

Blaine made a disgruntled noise, and his red-lipped pout was almost enough to break Kurt's weak resolve.

"Honey, we have to go back out there in approximately 2 minutes and I'm pretty sure the entire school will be able to see your hard-on in those pants."

Blaine looked down in surprise and Kurt nearly laughed out loud. As it was, he made a strangled noise in the back of his throat that earned him a glare from Blaine.

"Don't care," he mumbled, once again zooming in on the expanse of smooth skin in front of him. Kurt sighed.

"I've already been through three bottles of concealer this week!" he huffed as Blaine teased a particularly sensitive spot with his tongue.

Blaine pulled back and looked at him with wide eyes. Then he ducked his head, his cheeks flushing faintly pink. "You… don't like it?"

Kurt let out a surprised bark of laughter. "Are you kidding?" he asked, cupping Blaine's cheek until he looked up at him from underneath his unfairly long lashes. Kurt's willpower faltered again.

He took a deep breath and forged on. "In case you haven't noticed, my jeans are equally as tight as yours." He gestured vaguely downward.

Blaine's eyes dropped briefly, before looking back up at Kurt with a dangerously dark glint in his eyes and that did not have the effect I was aiming for, Kurt thought in exasperation.

Finally, he decided to try a different approach. He grabbed Blaine's collar and pulled him closer until their lips met, sweeping his tongue across his lower lip before sucking Blaine's tongue into his mouth. Blaine whimpered and gripped Kurt's hips roughly. Before he could get too worked up, Kurt pulled away to skim his lips across Blaine's slightly scruffy jaw to his ear.

He flicked his tongue out softly before murmuring, his breath brushing across the wet skin and making Blaine shiver, "I'll make you a deal. When we get home, you can leave hickeys anywhere you want — as long as they're somewhere no one else can see." He leaned back, quirking an eyebrow, to meet Blaine's wide eyes.

Kurt never had to use concealer again.