It came to him all of a sudden, hitting him like a zap of electricity and rendering him speechless - wonderfully, awestruck speechless - for a long moment as the realisation of something he'd known deep down for a number of years now solidified inside of him before being set in stone.

He didn't know what really triggered it; they hadn't been doing anything particularly special that evening: they weren't out on a date, they hadn't just experienced some life-altering moment, they hadn't even been making big proclamations of love to each other, it was just a lazy Sunday evening in their apartment. Blaine was lounging on the couch with his legs slung over Kurt's lap as he flicked through the issue of Vogue that Kurt had left on the coffee table while Kurt tapped the end of a pen against the corner of his mouth as he tried to write a shopping list for when Blaine went to the grocery store tomorrow.

Lightly patting Blaine's thigh where it was draped over his lap, Kurt frowned thoughtfully down at his list. "Can you think of anything we need from the store, honey?" He lifted his gaze from his list to look down at his boyfriend.

Lowering his magazine, Blaine stared at him for a moment, a small frown scrunching his forehead as he thought. He hummed in contemplation. "We're running low on that cereal you like," he replied eventually.

Kurt nodded as he scanned his list to check whether he had included that already. He tapped his pen against where it was written on the page. "I've got that - you let me know the box was nearly finished when you made me breakfast yesterday," he reminded Blaine.

Blaine hummed again in acknowledgement, there was a pause as they both thought, and then, "I need some more hair gel."

Sighing fondly, Kurt lowered his pen from where he had been holding it poised over the page. "I thought we were weaning you off that so you stopped drenching your hair in it."

"I'm hardly wearing any today," Blaine pointed out mildly. "And there's only a small amount left."

"It's only a small amount if you go back to plastering your hair down with it again."

"Kuuurt," Blaine whined pleadingly, pouting at his boyfriend over the top of his magazine.

Groaning at his own inability to resist, Kurt added the hair gel to the end of the list. "Fine." He shook his head, but was unable to hold back a smile as Blaine beamed at him before returning to his magazine.

Kurt didn't know whether it was the simple domesticity of the moment, the way Blaine had smiled lazily and adoringly at him, the pleasant squeeze in his stomach and increase of his heart rate as his eyes had taken in the way Blaine had unconsciously nibbled on his bottom lip whilst he read an article in the magazine, how breathtakingly beautiful his boyfriend looked lounging on the couch with the low lighting shadowing his face, or whether it was something that had been building up inside of him for so long demanding to be noticed and that little moment between them, familiar, but still cherished, caused the realisation to hit him and make the air rush from his lungs as his heart stuttered over a beat. It hit him right there and then as he finished adding the last item to the list and shot a fond smile at his boyfriend: he wanted to marry Blaine, he wanted to go out and buy a ring and propose to the man he had loved for years.

He had never been able to imagine life without Blaine since the day he'd met him, but it was only now that it was really hitting him that he wanted to marry him, wanted to spend every Sunday with Blaine's legs draped over his lap and his soft breathing filling the air as they wrote out what they needed to buy from the grocery store. He didn't doubt Blaine's answer to the proposal, he knew Blaine wanted to get married one day, and if there was something he was absolutely certain of in his life it was his boyfriend and their love for each other.

Kurt offered to go to the grocery store the next day, brushing off Blaine's protests about how it was his turn; he had something else he needed to buy and this was his chance to go shopping for it alone. He stopped by several jewellers while he was out, critically examining their range of rings under the watchful eyes of eagerly hovering salespeople, but it wasn't until he visited a small store set in a street busy with New Yorkers out shopping that he found the perfect one.

It was a perfect match for Blaine: classy and beautiful while not being over-the-top. Made of white gold with a few small diamonds set in the band, it caught the eye as it sparkled softly under the lights.

He pointed it out to the salesman. "That one," he breathed as he stared at it, enamoured. "That's the one."

The perfect moment to propose came on their next lazy evening together, three days after he bought the ring on a Thursday after a busy day at their respective jobs. He had been carrying the ring in its little box around in a pocket since he'd purchased it so whenever the right moment presented itself he would be ready to ask the most important question of their lives. He didn't prepare a speech or a grand, intricately thought-out way of asking; he spent most of his life being theatrical and his relationship wasn't a scene in one of his performances, so he wanted it to be an unrehearsed, quiet moment between them, like all the best memories they had together were.

That perfect moment came when they'd finished clearing up after dinner and had moved through to the living room to flick through the TV channels or watch a movie if nothing good was on. Blaine had just declared that there was nothing worth watching on TV and had tossed the remote aside while Kurt eyed their neat stacks of DVDs contemplatively, trying to decide what he was in the mood for. He was just about to suggest a few titles when Blaine jumped to his feet.

"I know what we can do," he announced brightly. "We can make your cookies!"

Kurt blinked up at him. "My cookies?" he repeated blankly.

His cluelessness only made Blaine's smile widen. "The ones I make you several times a year," he explained. "Your promise cookies."

It was the mention of the cookies Blaine had promised to make him at least twice a year as he had presented Kurt with a promise ring during their first Christmas together that made the moment perfect.

He didn't remember nodding and smiling agreeably at Blaine and he didn't really remember getting to his feet as Blaine turned to head into the kitchen. The next thing he was really aware of doing was slipping his hand into his pocket and pulling out that little box.

"Blaine?" he called softly.

His boyfriend immediately spun around to face him, his hazel eyes bright, his smile crinkling the skin at their corners.

The words came to Kurt without any real conscious thought. He moved closer to his boyfriend and held out his hand with the box in it. "Hello, I'm Kurt Hummel and I'll be auditioning for the role of your husband."

As Blaine's smile melted into an expression of shock, his eyes widening and his lips parting, Kurt dropped down onto one knee.

"Kurt, wh-"

Kurt opened the box with shaking fingers so Blaine could see the ring inside. Blaine was now visibly trembling as he lifted a hand to his mouth.

"K- Kurt-" he gasped.

"Blaine Devon Anderson," Kurt said calmly, his body quivering so much he wobbled slightly on the knee he was balanced on, "will you marry me?"

Blaine's eyes filled with tears as he continued to stare in shock, his hand still covering his mouth and his body still noticeably shaking. Kurt smiled up at him tearfully and as the first tears began to trickle down Blaine's cheeks, his boyfriend responded.

 Blaine let out a watery chuckle and fell to his knees in front of Kurt, pulling him into his arms and kissing him over and over again as their tears smeared together across their cheeks.

"Yes, Kurt. Yes, I'll marry you. Oh God, I can't believe- I love you, Kurt, I love you so much," Blaine babbled as he continued to kiss any part of Kurt's face he could reach, his words stumbling over each other slightly in his haste to get them out.

Kurt chuckled in delight, his heart swelling with a happiness greater than anything he had ever felt before and his face almost aching from smiling. He kissed Blaine again, letting his mouth linger against his new fiancé's lips. "I love you, too, Blaine; the day I met you on that staircase at Dalton I knew you would be special to me."

They held each other and murmured soft declarations of love, whispers of adoration, and expressions of delight as tears of joy trickled down their cheeks. They were engaged to be married, were the happiest they had ever been, and it had all come from a lazy Sunday, a shopping list, promise cookies, and years of being each other's best friends and soulmates.