The first time you told Sirius Black you wanted to become an Animagus, he nearly choked on his pumpkin juice.

“You?” he’d sputtered across the Gryffindor common room, wide-eyed and half-laughing. “You want to become an Animagus? Do you even know how impossible that is?”

But you didn’t flinch. You met his teasing gaze squarely and said, “You managed it. How hard can it be?”

That wiped the smirk clean off his face. For once, Sirius didn’t have a snappy comeback. He just blinked, a strange glint in his eye—something halfway between amusement and curiosity.

“Let’s see if you can manage something besides studying and worrying,” he’d teased, his gray eyes gleaming with mischief as he leaned against the desk, arms crossed. “A ferret, you said? That’s ambitious. Cute, though. Suits you.”

You’d rolled your eyes. “I’m serious about this.”

“No, I’m Sirius.”

You hadn’t laughed. He had. And yet he’d shown up the next night with an old book, scribbled notes, and the beginnings of a plan.

And so it began.

Sirius insisted the first step was to learn the theory behind the magic, but it was clear from day one that he preferred hands-on chaos to careful study. Your first attempt with the Mandrake leaf nearly turned into a disaster when he distracted you by trying to balance three books on his head “to break the tension.” That was Sirius for you—brilliant, infuriating, and always three steps away from trouble.

You met in secret: abandoned classrooms, corners of the library no one dared to use, the edge of the Forbidden Forest when the moon was thin and Remus was safely away. It was reckless, stupid, and absolutely exhilarating. Sirius was a terrible teacher by any traditional standard, but he made it fun. He made it feel possible.

And he kept showing up.

That part surprised you the most. At first, you thought he’d grow bored and drop the whole thing after a few weeks. But he didn’t. If anything, he became more invested. He memorized parts of the transformation theory, tested your reaction times, quizzed you when you were least expecting it. He’d laugh when your nose twitched involuntarily and call you “Whiskers” with an obnoxious grin. But he also started carrying extra potions in case your attempts left you dizzy, and he always stood between you and anyone else when you looked too pale or drained to walk back to the common room alone.

“You know,” Remus said casually one afternoon as he caught you two sneaking back into the library wing, “it almost looks like you care, Padfoot.”

Sirius had thrown a rolled-up piece of parchment at his head, muttering, “Bugger off, Moony,” but he was pink at the ears for the rest of the evening.

Truth was, you didn’t fully understand why he was helping. He said it was for the challenge, to see if someone else could do what he and James had pulled off. But when you had a particularly bad attempt in your sixth week and collapsed halfway through the partial shift—skin crawling, muscles spasming—he was the one who caught you. Sirius, not James. Sirius, who didn’t laugh. Who didn’t smirk.

He just held you, quietly, as your breathing evened out.

“You’re not doing this to prove anything to anyone, yeah?” he murmured, brushing your hair out of your face with a kind of gentle hesitance. “Just… don’t break yourself trying.”