Posted originally on the Archive_of_Our_Own at https://archiveofourown.org/ works/6347596. Rating: Explicit Archive Warning: Underage Category: M/M Fandom: Harry_Potter_-_J._K._Rowling Relationship: Sirius_Black/Remus_Lupin, Sirius_Black_&_Remus_Lupin Character: Sirius_Black, Remus_Lupin, James_Potter Additional Tags: Gay_Sex, Vibrators, Teacher-Student_Relationship, Alternate_Universe_- Student/Teacher, Nipples, Nipple_Licking, Nipple_Play, Butt_Plugs, vibrating_butt_plug, First_Time, Multiple_Orgasms, Comfort, Smut, Eventual_Smut, Underage_Sex, Consensual_Underage_Sex, Underage_Kissing, Loss_of_Virginity Stats: Published: 2016-03-25 Words: 2217 ****** You Have To Earn It ****** by DarkEchoes Summary Sirius Black is in a secret relationship. Not even James Potter, Sirius's best friend, knows about it. That's because he's in a relationship with Remus Lupin, his English professor. Sirius says he wants to go all the way with Remus. Remus agrees to it, but only as long as Sirius can sit quietly in his class for one day. Sirius agrees, but there's a catch.      Sirius moaned loudly as Remus kissed his chest softly, flicking his tongue over the younger's nipple.       "R-Remus..." He arched up against his professor, tugging on the button of his jeans. Remus glanced up at Sirius and shook his head slightly, pushing Sirius' hand down and pining it above his head. He moved his other hand down to pinch Sirius's nipple, lightly sucking the other one. Sirius whimpered writhing under Remus's hands, wanting to be touched but shying away from the intense feeling. Remus bit down softly and then pulled away, gazing down at Sirius.       "You're so pretty..." Remus murmured and slid his hand down Sirius's body, stopping at his hip.       "Remus, please..." Remus glanced up at him and then back down at his cock, tracing a soft circle around the base with his forefinger. Sirius bucked his hips up and Remus pulled his hand away.      "I think you can get yourself off. I have to be at work in an hour."      "I have to be at school in two hours." Sirius pointed out and Remus smiled.      "I know. I watch you come in late everyday."      "My first period teacher doesn't mind." Remus rolled his eyes but bent down, pressing his lips to Sirius's. Sirius wrapped his hand around the back of his neck and parted his lips, letting Remus slip his tongue in. Sirius moaned as Remus's hand explored his body, finally stopping to wrap around his erection. Sirius tilted his head back and Remus nibbled his jaw, quickly pumping his hand around his student's cock. Sirius gasped loudly as his hips jerked upwards and he came on his stomach. Remus lifted his hand and licked the cum off, then sat back on his feet.      "I need to go get ready."      "Why don't you ever fuck me?" Sirius whined and Remus eyed him lustfully. "I know you want to."      "I do." Remus confessed and Sirius waited for an explanation. "I don't think you've earned it yet." Sirius rolled his eyes and Remus stared at him for a moment. "You can't even last for ten minutes when I'm only touching your nipples."      "Fine... What can I do to earn it?" Remus smiled slightly and looked down at Sirius's ass.       "How many classes do you have after mine?"      "None."       "Perfect." Remus said and Sirius raised an eyebrow. Remus hopped off the bed and walked over to the closet, shifting through the clothes and humming thoughtfully.       "I could write an essay on why you should fuck me?" Sirius suggested and Remus laughed.      "No, that's too easy..." He reached up and grabbed a small box off one of the shelves. "Be completely silent during my class today."      "Okay... I can do that." Sirius started to sit up and Remus shook his head. He opened the box and pulled out a small object. He held it up for a moment and then tossed it to Sirius.      "With this inside you." He said and Sirius grinned.      "A butt plug? Make it a little bit of a challenge." Remus stared at Sirius and pulled another small object out of the box, pressing a button on it quickly. The plug started vibrating in Sirius' hand and Sirius bit his lip.      "I'll keep the remote and change the speed whenever I feel like I should."      "What are the speeds?" Sirius chewed his lip as Remus showed him how fast it could go. "Oh... Um... Won't it like... Rub my prostate if I'm sitting?" Remus nodded. "Okay..."      "If you can't handle it you can stand up and leave. I'll turn it off for you, but if you give up..." Sirius stared down at the plug, heart pounding in his chest.       "Okay. I-I can do it." Remus smiled and walked back over to the bed. He bent down and pecked Sirius's lips, grabbing a bottle of lube and handing it to Sirius. "You aren't going to help me?"      "I want to watch you." Remus said and Sirius nodded slightly. He squirted some lube on his fingers and pushed them against his hole. He bit his lip and pushed one in slowly, toes curling. He moved it in and out carefully, then forced another finger in, whimpering slightly. Remus ran his tongue over his bottom lip as he watched Sirius scissor himself open. Sirius pulled his fingers out and grabbed the plug, coating it in lube before slowly inserting it. He finally got it all the way in and let his hand drop, shutting his eyes and sighing.      "What about my other classes?"      "I'll only turn it on in my class. I promise." Remus muttered and kissed Sirius's forehead. "I have to go to work now. Oh, figure out how to hide your erection." Remus blew him a kiss and then left the room. Sirius let his head fall back on the pillow and let out a shaky sigh. He could do this. He could definitely... Hopefully do this.      Sirius was already on edge by the time last period rolled around. He almost considered skipping it, but Remus would obviously find out and... Who knew what he'd do?      "Sirius!" James said happily and clapped him on the back. Sirius tensed and then forced back a moan. "Are you okay? You look horrible."      "Yeah, just feeling a bit under the weather." Sirius muttered and James grinned.      "Couldn't stay away from Professor Lupin?" Sirius sighed deeply. James knew that Sirius liked Remus. Everyone knew. Sirius flirted with him constantly, even after they finally got together. He couldn't just stop. Everyone would know something was up.      "Well I couldn't miss a day. He would be worried sick!" Sirius joked and James laughed. "But yeah... He's just to hot."       "I bet if he wasn't a teacher you guys would be banging." Sirius laughed.      "Yeah, I wish..." Sirius mumbled as they entered the classroom. "What I would do to have his cock destroying my asshole." James laughed as Remus glanced up from his book to scowl at them.      "Why do you always come in here saying the foulest things?" Sirius grinned at him and sat down on his his desk, reaching a hand out to stroke Remus's wrist.       "Because I want to turn you on." He glanced down at Remus's pants, checking for a bulge. He saw Remus slip his hand into his pocket and the plug in Sirius's ass started vibrating. Sirius went rigid and stared down at Remus, who only smiled at him.      "Try harder next time." A chorus of "oooh's" spread through the class and Sirius hung his head in defeat, hopping off the desk and trudging to his desk. He slipped into the chair and held his head up with his hand, chewing on his finger. Remus waited for everyone to sit down before he stood up and started class. When he wasn't using his hand to point at something written on the board or make gestures, he would slip it into his pocket and turn up the speed.      He read a chapter from the book they were reading and then cleared his throat, glancing over at Sirius, who was hunched over his desk, backpack resting in his lap and finger in between his teeth.       "Partner up and discuss the chapter." James skipped over to Sirius and pulled a chair up to the side of the desk, sitting down with the back of the chair between his legs and head resting on his hand. He eyed Sirius and then laughed.      "Lesson too much for you?" He asked, nodding at the backpack in Sirius's lap. Sirius's face turned red and he stared down at the desk.      "Yeah, I mean... Professor Lupin's voice is just so sexy." Remus looked over at Sirius, who waved at him. "Oh, he's coming over here." Remus walked over to the desk and crossed his arms over his chest, staring down at the two boys.      "Give me a summary of the chapter." James opened his mouth but Remus held a hand up. "No, I want Sirius to."      "I'm sorry professor, but... I wasn't paying attention. At least not to the book." The vibrations sped up and Sirius squeezed his eyes shut. "Maybe next time." He forced out and Remus stared at him.       "Stay after the bell. Until then, James, tell him what happened."      "Yes, sir." Sirius muttered, biting down on his lip. Remus hesitated a moment before turning and slowly walking away. He sat down on the edge of his desk and surveyed the classroom. He caught Sirius's eyes and turned the vibrator up all the way. Sirius chocked back a groan as he erupted in his pants. He shot out of the chair and rushed to the front of the classroom, heading for the door.      "Going somewhere?" Remus asked, sounding slightly disappointed.      "Y-Yeah, I... I need to get a drink."      "There are only four minutes left. Can't you wait?" Sirius bit his lip, shoving his hands in his pockets to hide the way his hands were shaking.       "Yes, sir. Sorry..." He walked back to the desk and sat down, ignoring the worried gazes all of his classmates shot him. James asked him something and he shrugged, not able to hear the question over the fuzziness in his brain.       "Are you okay?" James's voice forced it's way through the haze and Sirius looked up at him.      "Yeah, just... Just feeling a bit sick." James nodded and started summarizing the chapter. He was halfway through when the bell rang.       "Feel better. Sorry you have to stay after the bell." He winked. Sirius smiled weakly. He had no idea... Sirius stayed in his chair as the rest of the students filed out of the room. As soon as they had all left, Remus stood up and locked the door.       "You did a great job." Remus started, motioning for Sirius to come to his desk. Sirius pulled himself up and stumbled towards him. "You almost gave up. Why?"      "I-I couldn't..." Remus brushed the back of his hand across Sirius's cheek, smiling gently.       "Can you wait until we get home?" Sirius whimpered. "Please? I'll do whatever you want." Remus purred, sliding his thumb over Sirius's bottom lip.       "I-I already came..."      "Can you come again?" Sirius nodded eagerly and Remus smiled, pecking his lips. "I'll speed home."      Remus helped Sirius out of the car and scooped him up in his arms, carrying him into the house and to the bedroom. He set him down on the bed and pulled his shirt off, flicking a finger over his nipple.       "R-Remus, please-" Sirius choked out, tugging on Remus's shirt. Remus stripped down quickly and then pulled Sirius's pants off. He pulled his briefs down, glancing up at Sirius as he saw the cum in them.       "You came twice?"      "In the car- Please, Remus. I need-"      "I know." Remus murmured, stroking Sirius's cheek. "I know." He pushed his lips to Sirius's, letting the other boy press them together. He reached down and gently pulled the plug out of Sirius's ass and Sirius cried out in relief.      "Thank you." He whispered and Remus nodded, kissing his jaw softly. Sirius glanced down at the lube and Remus grabbed it, quickly coating himself. He leaned down and connected their lips, pushing in slowly. Sirius moaned loudly and pushed against him, nails scratching Remus's back.      Remus thrust his hips quickly, craning his neck to suck and bite at Sirius's neck. Sirius arched his back up against Remus', snaking his legs around his waist to pulled them closer. Sirius cried out as he came for the third time, his whole body shaking like a leaf. Remus continued to thrust into him, hands pinching his lovers nipples, pulling him towards another orgasm. Remus snapped his hips forward, slamming into Sirius's prostate as he came inside him with a loud moan.      "Remus!" Sirius sobbed a second later as he spilled onto their stomachs. He dug his nails further into Remus's back, crying softly into his shoulder. Remus pulled out slowly and unhooked Sirius's legs from his waist, twisting his neck to kiss the side of Sirius's head.      "Did I hurt you?" He asked and Sirius could only manage to shake his head against Remus's arm, still crying softly. "Are you sure?" Sirius pulled Remus down beside him hiding his face in his chest. Remus wrapped his arms around the younger man, kissing the top of his head. "I'm sorry." Sirius shook his head and waited a moment. He lifted his hand up and wiped his eyes, then looked up at Remus.      "I-I'm okay... Just... It felt so good..." Sirius ducked his head down and Remus sighed, pulling his chin back up.      "Don't get shy now." Sirius bit his lip and nodded. "What's wrong?"      "I should have told you that... I was a virgin?" Remus stared at him for a moment before he smiled.      "You thought I didn't know?" Sirius looked down. "I knew before but now that I've..." Sirius's face grew redder. "I enjoyed it."      "I did, too..."      "I know." Remus chuckled and Sirius laughed slightly. "You might want to stay home tomorrow. You'll probably be a bit sore... I'll tell the rest of the teachers that you were sick." Sirius whispered a small thank you and rested his forehead back on Remus's chest. Remus felt his breathing slow down and smiled fondly, kissing the top of his head. "I love you..." Please drop_by_the_archive_and_comment to let the author know if you enjoyed their work!