Remus couldn't believe his ears. He felt warm all over, and knew his cheeks were burning pink. Sirius loved him. How long had he thought about what it would be like to hear those words? He never expected them to be said, and now that they had been he didn't know what to do. He felt like he was flying, and sort of like he'd just been hit by a Muggle bus.
His gaze dropped to their joined hands, then lifted to meet Sirius' eyes. He could see the desperation there, and it pained him to think that Sirius felt that way. Expressing love should come from a happy place, and he wished that such devastating circumstances hadn't had to take place in order for these feelings to be propelled out of both of them, but he also wouldn't trade it for anything in the world.
"I've been in love with you for a long time," he finally said. There was so much he wanted to attach to that statement. He wasn't good enough for Sirius; Sirius deserved better than anything he could offer him; there were others out there who could probably make him happier than Remus ever could. But there was one thing that he knew right down to his core. No one could love Sirius more than he loved him. Sirius said it himself; he could be him and still be loved all the same. Remus understood that, and believed it. So maybe loving him was enough. There was still a lot of healing to do, but for now, he just wanted to shut his brain off.
"And this is just ours. Moony and Padfoot," he said, and squeezed the other boy's hand. "No one can take that away from us."