Disclaimer- Sirius Black and anything recognisable is not mine. Persephone Scamander, however, and the plot is.
This is what happened "the night" in Speeding Cars, Enjoy...
I Felt You In My Legs Before I Even Met You. And When I Lie Beside You For The First Time, I Told You. I Can Feel You In My Heart But I Don't Really Know You. And Now We're Saying Bye. I Was Nineteen So Call Me. I Felt You In My Life Before I Ever Thought To. Feel The Need To Lay Down Beside You And Tell You. And Now We're Saying Bye. Bye. Flew Home Back To Where We Met. Stayed Inside I Was So Upset. Cooked Up A Plan So Good Except I Was Alone. You Are All I Have. You Were All Mine, I Was Yours, Right? -"Nineteen" Tegan and Sara
Sirius woke, sweating. Persephone was screaming.
"Shit," he breathed, jumping out of bed, adrenaline running through his veins. She wasn't stopping for breath. He dashed into the bedroom opposite his own, the door slamming open. Persephone was alone, lying on her back. Her eyes were open and she was screaming at nothing. "Sephie!" He yelled, shaking her. Her eyes were staring straight through him. "Sephie! Wake up!" She stopped. Her eyes closed and so did her mouth, in a small smile. Like she was happy...Suddenly she gasped as if she'd just beein drowning, her chest rose dramatically and her eyes flickered open. She was gasping for air, her eyes terrified, her hands gripping at Sirius. "Sephie! Sephie!" He was trying to calm her down, trying to hold her shoulders, he gripped her face between his hands. "Sephie, it's me, Sephie, calm down. It's okay...It's okay..."
"Sirius..." she breathed, her gasping calming down. "Sirius...What happened? What was it?"
"A dream, Seph..." he brushed her hair out of her face. "It was a dream. Don't worry. Noone's here except me and you." Sephie suddenly sat up and grabbed Sirius in a hug. He put his arms around her. "Seph, what was it? Seph, please calm down."
"Please don't leave me..." she mumbled into his shoulder. He sighed filled his hand with her hair. "Okay...okay..". They stayed like this for a few seconds in silence. Sephie wasn't crying. Sirius had never really seen her cry. She was always too busy being a panda. At least she wasn't upset this time.. She pulled back after a second, pushing her hair behind her ears, looking into her lap. "Sorry I got you up," she mumbled. Sirius smiled sympathetically. "Don't worry about it. I wasn't sleeping that well anyway." Sephie looked up and gave him the same look she did after she turned back from a panda. He didn't know what came over him. But he did it so fast he nearly headbutted her. The only thing he thought of was Well, this is different... The most he'd got from kissing girls was a few butterflies if it was someone particularly good-looking. Usually he didn't even get that. But this was...crazy. He had butterflies, but not just in his stomach. He had butterflies in his veins. He felt as light as a feather. Which is probably why he didn't realise how hard he leaned her back onto the bed.
Her head hit the pillow, her hair spreading out around her as his hands hit the pillow either side of her face. Both their eyes were closed and Sirius was heavy on top of her but she didn't care. Her hands were too busy, one feeling the black floppy hair that met the nape of his neck, the other was gripping the toned arm as she wiggled her fingers up his t-shirt sleeve to his shoulder. One of his hands pushed hair out of her face as he pulled back slightly, opening his eyes as her did the same, pleading with him not to. "Seph..Seph.." he breathed heavily, before moving down to kiss her neck gently. He couldn't deny when she looked at him like that..."You're not gonna stop me this time, are you?" he breathed in her ear as her fingers clenched his hair.
"No..." she moaned, his hand trailing down her body to her hips, grabbing at her wantingly. He grinned, before continuing his assault on her neck, trailing kisses from her jawline and along her collar bone. But he didn't just want to...do her. He wanted to fall through her...that's the only way he could describe his feelings. He wanted her so much. He wanted to get closer and closer...Her hands moved down to the hem of his white t-shirt as his found her own, his fingers trailing across her stomach teasingly. His shirt was pulled off his back, his hair meesing up, and Sephie grinned as she pulled him back down to her lips. Sirius didn't think about what he was doing, he let himself feel the parts of her he wanted, kiss how he wanted, and he didn't think what would happen after he did this. His best friend. Persephone, and him. He didn't care. He let any feelings he'd had over the past four years to the surface, and all they wanted was to show her...everything. His hand pushed up her black t-shirt, pulled it over her head, parting the kiss, their eyes opening to stare into each other before they reunited lips. His hand traced her collar bone, the same way it had that time at Hogwarts, and sent shivers down Persephone-good ones. Very good ones. He didn't think about her being naked as he tugged at her pyjama shorts, pulling them down as she kicked them off, slipping her underwear off with them. Sephie's small hands gripped his back as they made their way down to his own boxers, hooking fingers under the waitsband before running them round to the front. Sirius moaned, and she grinned, letting go off the boxers without removing them..."Seph.." he begged, parting lips so he could kiss her collar. She smiled again, before whipping his boxers down. The room was pitch black almost, but their eyes adjusted to see each other. Sirius's hand was beside her face, holding him up as his other hand was causing the moans to erupt from Sephie's chest.
"Please..."she breathed in Sirius's ear, and he tilted his head to talk in hers. "Sure?" he asked, but didn't want to give her the chance to say no. She nodded, not even thinking, and he removed his fingers and slid into her.
"Fucking.." she breathed, not being able to finish the sentance, her head tilting back as Sirius groaned. He moved his lips back down to her neck, the subtle smell of her perfume still on her, but not overpowering. He'd only be able to smell it if he was this close. Her hands gripped his shoulders, feeling them flex and move with him, his breath warm on her neck. He was starting to sweat, his hair getting wet on his forehead. She moved a hand up to his brow and brushed his fringe aside, his face now infront of hers. His eyes opened and looked deep into hers. Neither sets were clouded. Sirius could see exactly what Sephie was feeling in the green irises, the pupils dilating to see him in the dark and the grey outline widening. A tendril of her hair had fallen across them, was caught on her lips. He lifted a hand and brushed it aside as she had done to him before replacing it beside her own arms, holding her shoulders tightly. Their foreheads met, their eyes still open, their mouths not connected but only milimeters apart as they breathed heavily. A bead of sweat ran down Sirius's face, Sephie bit her lip to try and silence her moans. They did live in a terraced house after all.
"Sirius..." she breathed, her fingertips digging into his back and neck as her eyes closed. Her body convulsed, her back arched and Sirius slipped his hand between her spine and the bed, holding her. Sirius closed his own eyes. "Shit.." he breathed back, closing his own eyes and crashing his head into her neck. He groaned, but didn't stop. He slowed. Carried on for a few moments before collapsing on top of her. Her hands wound into his hair, stroked his head gently. His breathing slowed with hers. He rolled off her and lie on his back beside, looking over at her. She turned her head to his, her eyes and his once again locked. She smiled, he returned it, and their mouths met again.
For half an hour they just lie in Sephie's bed, kissing, cuddling, hands holding each other. Sirius and Persephone had finally, well, done it. Her hands were on his face, they were looking at each other in silence, his arms were around her waist tightly. One of her hands trailed down his chest, down his stomach, and he grinned. Gripped her hips and pulled her ontop of him. She giggled, the covers now over them. Her hair was curlier than usual, and messed up. Sirius's was slightly wet from sweat, and all over the place. He watched her face as he pulled her down and lifted her, eyes closed and teeth biting her bottom lip. She placed her hand either side of his chest, and pushed herself. Sirius closed his eyes, moved his hands up her back, felt the dip of her spine. It was slightly damp, but soft none the less. He scrunched her hair in his hand, stroked her cheek. It didn't take long. Sephie slammed her hands on Sirius's chest as he moaned. He pulled her down to kiss him, held her to him. They fell asleep after a few moments.