A/N
Right, flashback because I'm the writer and I wanna write angst but I can't do that in the current time and this is my book and I decide what to write!
So first kiss from Sirius's POV.

Sirius, finally having plucked up the courage to pull Remus aside, grabbed the werewolf's hand, taking him away from the bustle of the party and to a quiet sofa near a snow-covered window.

Remus shot Sirius a questioning look as he was guided onto the seat. Sirius didn't speak, however, until he too was seated.
"I actually have another gift for you, Remus." His voice was bordering on hesitation, his tone almost unsure.

Their eyes met as he pulled the present from his robes. He held it out for Remus to take. Remus gently unwrapped it, careful not to rip any of the snowflake-adorned paper. His brows knitted into a frown when he saw the book Fantastic Beasts and Where to Find Them.

"Sirius, I already have this book..." Sirius fought to swallow the short burst of panic that rose in his throat, forcing a warm smile on his face. He knew Remus already had the book; after all, this was just a few pages different from the original.

"Open it to the werewolf chapter." Remus's frown deepened as he turned the page. Sirius held his breath as the werewolf's eyes widened, begging, pleading for Remus to like it. His courage faded as his thoughts spiralled.

Was it too forward?
Did Remus even like him?
This was a stupid gift...

A tear rolled down Remus's face. For a moment, Sirius thought this might have confirmed his fears. But something amazing happened - Remus's breath hitched, a small, watery smile appearing on his face. Sirius realised the tear had not been sadness or anger, but rather... happiness.

He cleared his throat, steadying himself.
"I... Remus, I like you. I've liked you since the moment I laid eyes on you, on the Hogwarts Express. You were all curled up in your seat, reading a book, and I just... Remus, I love you." He closed his eyes, bracing for rejection. What he heard instead was nothing like the regret he thought he might feel.

"Wha-what? You're... I... I love you too, Sirius..."

Sirius let out a breath, relief flooding him, his heart swelling with a joy he hadn't known was possible. He leaned close. Remus gave a small gasp before he too moved in. Their movement was hesitant as their eyes met, Sirius's gaze darting to Remus's lips before he pressed them to his own.

The kiss was tender, sweet. Remus tasted of chocolate and warm fires, of safety. All too soon, they were leaning back, and Sirius exhaled deeply. He felt Remus's hand brush his; before he could tell himself not to, he flinched back.

Remus continued to stare out the window, though his eyes were glazed over, a slight glint of moisture in them. Sirius placed his hand on Remus's, watching how the boy's eyes flickered from the window to their intertwined fingers.

Sirius gave him a small, reassuring smile, and the werewolf visibly relaxed. Sirius felt Remus tighten his grip, almost as if he were afraid Sirius would float away. Sirius squeezed back. The world narrowed to two teenage boys, their hands interlaced, and everything was okay.

A/N
If you liked this, it'd mean the world to me if you checked out my other book 'Bound By Scales: A Dark Trio Story'