(A/N): Hey Guys! So, this is only my second attempt at slash, and my first attempt at any type of sex. So uh, I hope you enjoy. Also, this story goes well with the song Casual Sex by My Darkest Days, for which I named it. Now, this story stars my OC from Into the Fire, Leo, and he's a half-vampire. You don't have to read that story to understand this one, though it is recommended. However, this is set in their sixth or seventh year and Into the Fire is only at first year so far. I was writing the next chapter and it had Sirius pleading in it, and this is what popped into my mind.

Disclaimer: I own nothing but Leo.


"Please?" Sirius pleaded, dropping to his knees in front of my chair in our deserted dorm room, and I smiled, thinking of the sexual implications that could be put behind that one word and the action he had put with it.

"No." I said stubbornly, the small smile I wore hidden by the pages of the book I held to me.

"Oh come on!" He groaned, pulling the book out of my hands. I could have resisted, if I had wanted to, but I found his tactics to be truly amusing.

"I'm still going to say no." I said quietly, staring him down as his forearms came to rest on my thighs, and I barely withheld a shiver.

"Why can't you just tell me?" He asked stubbornly and I rolled my eyes.

"You've been on about his since first year, why can't you just let it go?" I muttered tiredly, trying to rub my forehead, only to have to push my long fringe out of my face.

"You need a hair-cut." Sirius noted amusedly and I looked at him with a 'no duh' expression.

"What, and you don't?" I retorted, leaning forward to grab a lock of his shaggy black hair before rolling it in my fingers.

"Well, at least I don't smell like raw steak." I froze for a second, but he didn't notice. Did he know? No, no one knew, there's no way he knows.

"Well you smell like wet dog." Now it was his turn to freeze. "Relax animagus boy, stress is slowly killing you." I took advantage of his frozenness to pull out from under his arms and start to move across the room to get changed. That is, before Sirius' arms gripped mine painfully and he pushed me into a wall. He had an arm on either side of me and his face was only a foot away from mine, wearing an enraged expression.

"How did you know I'm an animagus?" He growled, his arms tensing on either side of me as I grinned at him easily, not at all scared of him.

"I told you, I know all secrets. Hell, I've known about Moony's furry little problem since well before you did." His expression calmed and he raised an eyebrow at me challengingly.

"Okay, what's my animagus?" I rolled my eyes at his question before opening my mouth to reply.

"That's too easy, it's a big black dog that looks like the grim." He blinked before going to ask another question.

"James-" I cut him off, crossing my arms over my chest in an almost cocky way, and I could see the anger rising on his face again.

"James is a stag and Peter is a Rat. Together you make the Marauders, Messrs Moony, Wormtail, Padfoot and Prongs are proud to present the Marauders map." I added the last bit and he went almost ghostly pale before glaring at me.

"How the hell do know that?" He asked through gritted teeth, and I could see the anger rising even further as I didn't answer. "You have to tell me or-" I cut him off, my head snapping up and I glared at him with full power, and he cringed. I was a hell of a lot more threatening than any human, except perhaps Lily, but he refused to back down. I could tell by his scent that he was scared, but he didn't give into it, he simply stood there.

"And what are you going to do about it? Hurt me? Persuade me to tell you?" I took a step forward until we were only an inch apart and stared him down, only now realising that I was an inch or two shorter than him. He seemed surprised at how quickly I had closed the distance between us, and he glanced down at the pitiful excuse for space between our bodies before looking back at my face, the anger almost completely wiped from his face, though not from mine. Suddenly, he was upon me, his lips covering mine in an almost airtight seal, and I let him push me back into the wall, startled.

I stood there, motionless, as his lips moved against mine passionately, stunned. After what felt like hours, though was probably less than a minute, he pulled away slightly to look into my eyes, which were still pressed shut. His breathing was heavy whereas mine was almost completely even, not having to breathe as much as regular humans did. I brought my hand up, and I could feel him watching it before I grabbed him by his tie, pulling him back to me in a heated kiss. My hand that had been gripping his tie slid to the back of his neck, and my other hand gripped his right hip, pulling him even closer to me, and he moaned quietly as the bare skin of our stomachs rubbed together, causing me to smirk into his mouth. He had one of his hands pressed into the small of my back and the other one rubbing circles between my shoulder blades.

I moved the hand that was on the back of his neck down to his shoulder before smirking evilly and dragging my semi-sharp nails down his chest, taking advantage as he opened his mouth to release a combination of a moan and a gasp and slotting my tongue inside, fighting his for dominance. Eventually, I won as he was distracted by flipping our position so that he was now the one pressed against the wall. I pulled my mouth away from his to trail kisses across his jaw and up and down his neck before placing a sloppy kiss on his ear, to which he shivered in pleasure. I moved my lips down his neck and smiled slightly before locking my lips onto his pulse point and started suckling at his skin there, eliciting a low moan to erupt from his lips. I started unbuttoning his shirt, seeing as he was still in his school uniform from today's lessons, whereas I had changed into a more comfortable outfit of a t-shirt and jeans. I pushed the shirt of his shoulders as his arms unwrapped themselves from where they had tangled themselves around my body and we let it fall to the floor before he tugged at the hem of my t-shirt and I grinned into his skin before nodding slightly, letting him pull it halfway off before moving back slightly so he could actually get it off. We collided again, barely holding back moans as our bare skin met, caressing the others with soft touches.

My lips locked over his collarbone, my hands running up and down his sides as his knuckles brushed my spine, making me shiver in pleasure before moaning quietly into his ear. Apparently, this turned him on for he pulled my lips back to his and pushed back to my kisses fiercely and passionately. He ran his fingers done my chest before raking his nails over my sensitive nipples, and I barely resisted gasping and moaning, which I knew was exactly what he wanted. I grinned as he groaned in frustration, feeling his member harden against my leg, and I pulled my lips away from his to trail wet kisses down his chest, muscled as it was from playing Quidditch. He moaned and his head tilted back, resting against the stone wall as I kneeled in front of him to kiss along his stomach, hips and v-lines. I paused for a second, breathing against his skin before grabbing the zipper to his pants in my teeth and dragging it open. His head snapped down to watch me and I looked up at him, smirking slightly as I saw his eyes glazed over with lust. I slowly reached inside his pants and boxers to stroke his member. Oh yes, those girls were definitely right, he was well-endowed. I smirked proudly as I thought, but he's not as big as me.

He let out a low groan as my fingers brushed his shaft and I smiled slightly before wrapping my fingers around him before dragging it up and down slowly and gently. His head was flung back once again and I shook my head lightly at his reaction before wrapping my lips around the head, using my tongue to spread his pre-cum around. His moans, louder this time, turned me on immensely and I took him in my mouth, swallowing him whole. He shivered and moaned again and I reached for my wand distractedly before casting Muffliato and a locking charm at the door silently before dropping it again. I began bopping my head up and down, wiggling my tongue against him and even hummed slightly, and by how loud his moans were getting, I'd say I was doing rather well. When he tangled his fingers in my hair I pulled away and stood up, leaving him staring at me confusedly. I pulled him close by his tie, which we still hadn't removed, and whispered in his ear.

"Your turn." I moved away, turning around to walk towards his bed before looking over my shoulder, beckoning him with my eyes, and when I had turned my head to the bed again, I felt his eyes rake over my arse. Well, all the better then. As I reached the bed, he spun me around and pushed me onto it before climbing on top of me, his pants now fully off, along with his boxers, our shoes having been shed long ago, leaving him completely naked except for the Gryffindor neck-tie he wore. Of course, I was still wearing my jeans, and he growled at the sight of an only half-naked me before he started trailing kisses down my chest before sucking and nibbling on my pert nipples, making me bite my lips in order to hold back a moan of pleasure.

"Are you sure?" Sirius asked quietly, almost so quiet that a human wouldn't be able to hear him, into the skin around my belly button. I chuckled, drawing his eyes upwards to my face.

"Am I sure? Of course I'm bloody sure, now fuck me till I'm raw or you'll never get this chance again." He seemed shocked by my colourful language and the graphic imagery it instilled, and it also made him very turned on. He lent down and gripped the zipper of my jeans in his teeth just as I had done and grinned up at me before pulling them off roughly and slowly pulling down my boxers before throwing them away. I watched with a smirk as he turned his attention to my hardened cock, his eyes widening before he glanced up at me, surprised that after all this time of him making fun of me by saying I had a small dick, I was actually bigger than him.

His lustful eyes turned back to my pulsating member before he breathed in and took me into his mouth. I let out a loud moan as my erection was surrounded by the wet warmth of his mouth and he hollowed his cheeks, allowing them to rub over my skin before dragged his teeth down my length and taking me whole, his lips brushing against the skin of my stomach as he did so. Like I did with him, he left me on the edge of cumming, reaching over to rummage in his drawer for something...a condom. He glanced at me as he held the condom up and saw me with my lip ensnared between my front teeth, trying to hold back the moans I had been building.

"I don't suppose you have any lube?" He asked quietly, his voice full of lust, and I could feel his eyes raking my body, lingering on my erect penis especially.

"Should be in my top drawer." I told him after swallowing down the moans so I could actually speak, and he hesitated for a second, looking like he didn't want to leave me here, especially in my state of undress, but climbed off the bed, making it only a few steps before freezing and turning around to look at me. I smiled at him innocently, guessing what he was thinking and he shook his head slowly before continuing.

He returned not half a minute later with the bottle of lube in his hand, the condom already fit over his cock and he prepped himself before squirting some of the lube on one of his fingers before positioning it at my untouched hole. He looked up to me for reassurance and I just stared at him.

"Well you're the one who's apparently done this before!" He whispered, gesturing to the half-full bottle of lube he held in one hand.

"Well I never exactly said I was a virgin, now did I?" I retorted before going to cross my arms over my chest, only to stop and gasp as he inserted his lubed finger into my rectum.

"Did it hurt?" He asked, concerned before I shook my head.

"Just caught me off guard, I guess. Then again, this is my first time being on this end." He raised an eyebrow before inserting a second finger and started scissoring his fingers, widening me.

"Oh yeah? Guys actually let you be on top?" I smirked at him cockily before replying.

"Letting me doesn't really some into the situation. I'm just the more dominant one." I winked at him and his grin faltered for a second and his eyes glazed over with lust again as he inserted a third finger, stretching my hole even further before he decided I was ready and pulled out his fingers before lining his dick up with my hole. He stared into my eyes, waiting for the green light and I smiled slightly before nodding, and he inserted his penis into me, causing me to gasp and yelp under my breath, my hands fisting the sheets of his bed.

"Did I hurt you?" He asked, concerned again and I shook my head, even though it had, slightly. He paused for a second before slowly pulling out of me and pushing back in. Pain soon turned to pleasure as he thrusted in and out of me faster and faster, harder and harder, and I moaned loudly, raking my fingers nails down his back as he hit my prostate. Our skin slapped together as my back arched and our hips met, our fingers tangled together and he pressed a sloppy kiss to my lips as his breathing got heavier and heavier, and I felt myself getting closer to the edge a few thrusts more and he erupted inside me and I came soon after. He pulled out of me and rolled off, making sure he didn't crush me with his weight, and pulled off his condom, throwing it into the waist basket on the floor between our beds.

"You may want to empty that before the House Elves do." I panted, and he chuckled before pulling me to his side, his arms wrapped around me. We stayed like that for a few minutes before I pulled away, and Sirius sat up, watching me.

"Where are you going?" I smiled at him slightly, starting to get dressed.

"James, Remus and Peter are probably on their way back here from the Library, and I'm pretty sure they won't appreciate coming back to find the door locked and us in bed together." He thought for a second before nodding. "Also...this can't be official." He stared at me for a second before his head drooped slightly in resignation. "This is frowned upon, and it wouldn't make sense for you to just suddenly give up your string of lovers to apparently go solo either. Perhaps...perhaps we should be friends with benefits?" His head snapped up and he stayed silent for a few seconds, considering it.

"I'd like that, I'd like it a lot." I smirked and raised an eyebrow.

"Judging by what we just did, you would, very much." He blushed slightly and I moved over to my own bed.

"Wait a minute, how did you know James, Remus and Peter are in the Library? Remus I get, but James and Peter never go in the Library." I stopped halfway between our beds and turned to answer him.

"Now, now Sirius, remember how this all started?"


(A/N): Feel free to point out any errors I made, and please review and/or check out my other stories.