HARRY POTTER • FANTASTIC BEASTS | ONE-SHOTS

He'll Kill Us Both {Sirius Black} [M]

Pairing: Sirius Black x Gryffindor!Female Reader

Summary: Being James Potter's twin sister is not easy when you're secretly dating his best friend...

●○●

The room is pitch black and quiet but (Y/N) has not lost track of the clock hanging on the wall opposite her bed. She tries to wait for it to strike midnight as calmly as possible but a pump of adrenaline is already making its way through her veins and she begins to feel impatient. It is impossible to stay still but the last thing she wants to do is make the wrong move and wake up her dormmates; she certainly does not need an interrogation right now. So far, she's been successful the numerous times she has snuck out of the room without drawing attention, except maybe for that one time when she was almost busted by Filch, but even then she handled it pretty well.

When it is finally time to go, (Y/N) gets out of bed quietly, slipping her shoes on and tiptoeing her way to the mirror. She can barely see her reflection but she tries to work with what she has, and she figures that brushing her hair and putting on a bit of perfume will do the trick. It's nothing too big, she's not going out to a fancy restaurant, but she wants to at least be presentable for whatever outcome she'll get as soon as she steps out the door.

She throws a coat across her shoulders and decides that she's ready to get going. The faster she leaves, the lesser chances she'll have of getting caught by-

"Where are you going?"

Bloody hell.

(Y/N) freezes on her spot. Lily is now sitting up on her bed, holding her weight on her left arm and squinting her sleepy eyes at the doorway. The door remains half open and (Y/N) considers leaving while pretending that she hadn't heard her but, knowing Lily, she wouldn't be surprised if the girl decides to follow her. She turns to the redhead with an apologetic smile. "Sorry, did I wake you?"

"Yeah," Lily replies. "What are you doing up so late?"

(Y/N) clears her throat. "I was just about to get something to eat. I can't sleep with an empty stomach."

Lily quirks a brow. "Seriously?"

"Yup."

Lily sighs in defeat while she settles back into her sleeping position. "You know what? I don't know if I believe you but I'm honestly too tired to care right now."

(Y/N) chuckles. "That's okay, just go back to sleep."

When she doesn't hear an answer, she assumes that Lily has fallen back into a deep slumber. (Y/N) lets out a breath unaware that she was holding it, then proceeds to exit the room while trying not to make any more sounds.

She knows the way by heart. She's done this so many times already that she does not need to look twice at which direction she's headed. She loves the quietness of the castle at this hour, and how comfortable she has gotten with the darkness of the halls. She's lucky that most portraits are sleeping and, when they're not, she sneaks past them as easily as spotting Hagrid in a crowd. It wasn't always like that but she's gotten to know them better with time. She learned from the best, after all.

When she arrives at the broom cupboard, It's empty aside from the brooms, mops, and other cleaning supplies. She rolls her eyes. Of course, he's not here yet.

"Am I too late?"

Sirius arrives almost twenty minutes later and finds (Y/N) leaning against the table pressed to the stone wall, reading the label from a gallon that she had found lying around. She looks up quickly and smirks. "Only a little bit."