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You received the letter as you were leaving Potions and heading to Herbology. It was a busy day, you really didn’t have time for dillydallying, so you opened it quickly in a deserted corridor.
Undercroft, midnight. There’s something we should try. I promise it will be fun.
- Sebastian
Your chest tightened. You knew you should say no, you had a big Defense Against the Dark Arts exam tomorrow and could use as much sleep as possible. However, Sebastian had an inexplicable hold over you. You couldn’t resist his strange, often dangerous whims. Herbology was a blur, you couldn’t focus as you wondered what he might have planned for that night. Last time you met him he had taught you something pretty useful, which made it easy to convince yourself that tonight’s rendezvous was a necessity — and probably more important than some exam.
After dinner you ran into Natty, who bounded over to you from across the hall. “Up for a little late night studying?” she asked. Last week you had taken her to the room of requirement to prepare for a Herbology midterm.
“Sorry, not tonight,” you paused, “Next time, though, I promise.”
Her eyes narrowed, “You have plans.” It wasn’t a question.
“Maybe I do,” you said playfully.
“And would these plans, if they were to exist, involve a certain Slytherin we both know and loathe?”
You felt yourself blush. “He’s not that bad.”
“Well, be careful. There’s something about that boy, I don’t think he’s telling you everything,” Natty lowered her voice.
“I will, don’t worry,” you smiled as she turned down the corridor that led to the Gryffindor common room.
You spent the remaining two hours until midnight holed up in the library, attempting to finish some homework. By the time the clock struck twelve you had barely finished one assignment. You made sure to keep your steps light and quiet as you made your way to the Undercroft. The memory of your last unfortunate interaction with Ominis was still fresh in your mind.
The door creaks open slowly and you make sure to shut it behind you. The place is as dark and foreboding as ever, the only light coming from a few flames hanging from the ceiling. You search the empty space for any sign of Sebastian, and finally spot him pacing at the back of the large room. As you get closer, you see that he’s holding a book open in both hands.
“Light reading?” you ask.
He looks up and grins, “You made it. I’m just making sure I don’t mess this up.”
“And what is this, exactly? Your letter wasn’t very illuminating.”
“Another spell,” he snapped the book shut and leaned against one of the large columns, “This one’s a little less fiery, but I think you’ll find it quite useful. It encourages the target to tell the truth.”
“I can see why that would be dangerous,” you chuckled.
Sebastian shrugged, “I don’t have anything to hide.”
“Wait, you want me to cast it on you?” you balked, staring at his smug face.
“You’ll cast it on me, then I’ll do the same to you. That way we can both practice.”
You were quiet for a moment. There were certainly things that you didn’t want Sebastian extracting from you. However, there was no way to back out now, not if you wanted to learn the spell. Besides, the prospect of getting to ask him a few questions wasn’t entirely unappealing.
“Alright,” you said, “Let’s do it.”
“Fantastic, I knew you’d come around.” He handed you an old book, presumably stolen from the library, and you read the page it was open to.
Once you were sure you knew the exact wand movements you looked up at Sebastian, who nodded. You raised your wand and spoke the incantation. A soft green glow emanated from the tip of your wand and floated towards him. When it made contact he stumbled a bit, but seemed unharmed.
“Sebastian? How do you feel?” you asked.
He shrugged, “Fine. A little disoriented, perhaps.”
You tried to think of an easy question to start with. Finally, you settled on one. “Where did you get this book?”
He smiled, “The restricted section.”
“How did you steal it?”
“I snuck down last night. It wasn’t easy, Peeves almost caught me again. I spent the whole time wishing you were there like the last time. It wasn’t nearly as fun alone.”
You laughed softly. The spell seemed to be working. “Speaking of the last time we were in the library, why did you take the fall for me?”
He stared at you and tilted his head, “I liked you and I didn’t think you deserved to get in trouble. Besides, I like the idea of you being in my debt.”
Your eyes widened. “Excuse me?”
“You owe me something now, and I like that.”
You felt your face getting warmer. “You never said anything about me owing you for that.”
He shrugged and stepped closer to you. “I was waiting for the right time.”
“What do you mean?”
“I know what I want.” His voice was low and quiet.
You took a shaky breath in. “And what’s that?”
“You.”
“Sebastian.” You stared at him in disbelief.
“I want you to give yourself to me. I’ve wanted that since the moment I saw you. I couldn’t believe my luck when you got put in Slytherin. I know you feel it too.” He was so close now; you had to look up to see his face.
“You’ve really wanted me this whole time?” you whispered.
He nodded, “I hated seeing you with Garreth at that party. He kept putting his arm around you and talking in that obnoxiously loud voice of his. I could’ve killed him, that’s how much I want you. You should belong to me.”
“Sebastian, I—”
“I think about you constantly.”
You were certain your face was bright red at this point. You could barely keep your breathing steady. You knew it was wrong, he didn’t really want to admit all of this, but you couldn’t resist. “What do you think about?” you asked.
“Touching you, making you feel so good you never want anyone else.”
“What else?”
“Your mouth, and how it would feel wrapped around me.” Sebastian had been steadily closing the distance between the two of you. Finally, he was just inches away. He lowered his head and you felt his mouth against your neck. His hand on your lower back held you against him. When his lips were right by your ear he whispered, “Your cunt, how tight you would be. How wet I could make you.”
You hated it, but he was right. Even now, with just a simple kiss on the neck, you were dripping for him. He turned his head to look at you. Your eyes met and you started to lean in. Just before your lips touched you snapped out of it. “Wait—” you scrambled to find where you had set down the book. As soon as you found it, you cast the spell to remove the charm. It had gone too far, you didn’t want him to do anything he might regret — no matter how much you wanted it.
Sebastian blinked and looked around. “Did it work?” he asked, seemingly back to normal.
“Um, yes,” you answered as you handed him the book.
“So, what did I say?”
“You told me how you stole the book and almost got caught by Peeves again.”
His eyebrows furrowed, “That’s it? Kind of a boring story.”
You let out a stiff laugh. “It was funny, you said that it would’ve been more fun if I had been there.”
You could’ve sworn he blushed a little. “Well, that much is true,” he said.
“You really don’t remember anything you said?”
He shook his head, “It feels like I blacked out. I saw you cast the spell, then the next thing I knew it was over. Are you ready?”
A wave of relief washed over you. As long as he didn’t remember, no harm was done and you could avoid any potential awkwardness. He cast the spell, and you watched the green light emerge from his wand and float towards you. It felt like being enveloped in warmth. Your limbs felt fluid and loose, almost like you were in a dream. Sebastian was watching you carefully.
“Y/n? Are you alright?” he asked.
“Yes, I kind of like it.”
He laughed. “Good. Now, why were you so friendly with Garreth the other night?”
“We’re friends and we were drunk.” The words tumbled out of your mouth of their own accord. No thoughts precede them. You heard them as if they were being spoken by a stranger.
“Do you like Garreth?” Sebastian asked, eyes narrowed.
“Yes, he’s my friend. But, no, not as more than a friend.”
“How come?”
You were quiet for a moment as you willed yourself not to speak. You didn’t want to say what you were about to, but there was no way to stop it. “There’s someone else.”
“Who?”
Every fiber of your being was screaming for you to stop. “You, Sebastian,” you said quietly.
He smiled, gloating. “Elaborate,” he said.
“I like you, a lot. It’s been that way for a while.”
“Why didn’t you say anything?”
“I didn’t know if you felt the same way.” This was beyond humiliating. You had been led to believe you would be blissfully unaware during this whole interrogation, but that was proving false.
“But you know now, don’t you?” He stared at you intently.
“Yes. You just told me.”
He stalked towards you. “And how did you feel, hearing me say all those things?”
You felt like you were on fire. Your voice came out hoarse and barely audible. “I felt like I didn’t want you to stop.”
“So, you want me to do this?” he asked and brushed your hair back to kiss your neck once more.
“Yes,” you whispered.
“What else do you want me to do?”
Your mind felt so scrambled you didn’t even care about your own shame or embarrassment anymore. “Kiss me,” you said.
Sebastian’s mouth met yours instantly. It was needy, but gentle. His hand held the side of your face. When he pulled away you stared up at him in shock.
“I know you’ve thought about me,” he said, “When you’re all alone, with your skirt pulled up, playing with yourself. Isn’t that right?”
“I have.” In the back of your mind you knew you were in for a world of regret later.
His hand slid up your thigh, under your skirt. You tensed. When his fingers brushed against the bare skin between your thighs, you shivered. His eyes widened for a moment. “Why aren’t you wearing anything underneath?”
“I wanted you to be able to bend me over and fuck me whenever you liked. I knew it wouldn’t happen, but I hoped it might.”
It was Sebastian’s turn to be shocked. He smirked and before you knew what was happening he had cast the removal spell. The trance was broken and the dreamlike state you had been in dissipated into dull reality. You no longer felt like you couldn’t control your voice, but you remembered every single thing you had said.
“You lied to me,” you breathed.
“You wouldn’t have done it if I hadn’t,” he said.
He was right. “It’s late, we should go to bed.”
Sebastian blinked. “Alright, lead the way.”
You felt unusually bold. Maybe it was because youI knew he wanted you too, or just because you had nothing else to lose tonight. You were already as humiliated as you could possibly get, so why stop there? You both walked in silence down the stairs to the Slytherin common room. It was empty, of course, being well past curfew. Sebastian sat down on one of the dark green couches and you sat next to him.
“What are you doing?” you asked, keeping your voice down.
“There’s a charm that prevents girls and boys from swapping rooms after curfew.”
“Oh,” you said, disappointed.
A sly grin spread across his face, “But as long as we stay down here, we’ll be fine.”
You looked at him. “Are you serious? In the common room? Anyone could walk in.”
“That’s part of the fun.” He placed a hand on your waist and pulled you onto his lap. You positioned yourself so you were facing him with your knees on either side of his thighs.
“Did you plan this? Is that why you chose that spell?” you asked.
He shrugged, “It crossed my mind.”
“Why don’t we just be honest with each other from now on?” you suggested.
“I’d like that.” His hands were under your skirt again. The warmth of his skin against yours was driving you crazy. You knew how wet you were and you hoped desperately that nothing was getting on his pants. When you leaned down to kiss him you knew there was no going back. You parted your lips and he did the same. Where it had been gentle before, now it was hungry and impatient. You felt his tongue slide over yours and you moaned softly.
His fingers rubbed against you in slow, deliberate circles. You shivered when he slid one into you, then slid it back out.
“You’re so wet for me,” he said, a hint of arrogance behind it. He teased your entrance, sliding the same finger in halfway, then pulling it out and repeating the process.
“More, please,” you sighed, aching with need.
“Tell me something first,” he said. The look on his face told you you weren’t going to like whatever was coming next. “Do you touch yourself like this?”
“Sometimes,” you said and felt your face flush.
“Have you thought about what it would be like to have my fingers in your tight little cunt?”
You nodded, “All the time.”
He looked satisfied, and you guessed he was as he slid two fingers into you. You felt yourself contract around them, thrilled by the new feeling of fullness. As soon as they had entered you, they were gone. Sebastian held his hand up. “Open your mouth,” he said. You did so and he placed those two fingers inside. You could taste how turned on you were, which only made you more excited. When he pulled them out he went in to kiss you. The tips of your ears burned even hotter knowing that he could taste you on your own tongue.
As he kissed you, you sunk down in his lap until you felt the hard line of his cock brush against you. You ground down against it and his breath caught. His hand grabbed your hip and squeezed. “Please, Sebastian,” you moaned. You had barely noticed, but he had undone the top few buttons of your shirt. When he bent to kiss your neck he began to play with your nipples. You pressed yourself against him and leaned into it. While he was busy, you reached down and unzipped his pants. Without being able to see much, you pulled his cock out from his pants and gave it a few slow strokes. You felt him shudder. You wished you weren’t in the common room so you could both fully undress. You wanted to feel him on every part of you.
You looked at each other and, as if you had some kind of psychic connection, both began to position yourselves so you were lying flat on your back and he was above you. Luckily, the couch was just big enough. Your skirt was rolled up around your waist, leaving you exposed to him. You would’ve been embarrassed if you hadn’t already reached that point a long time ago.
Sebastian leaned so his face was in the crook of your neck. You could feel him, hard and leaking, pressed against your entrance. “Tell me your mine,” he said, sounding almost pained.
“I’m yours, Sebastian, I’ve always been yours.”
When you felt the tip of his cock glide into you you couldn’t help the moan that escaped you. He was big, you could already tell. He slid in further, stretching you more than you had ever experienced before. “Please,” you begged.
With that he shoved the entirety of his cock into you and stilled. The pressure was wonderful, you had never felt so full. You whimpered and arched your back as he began to thrust. The hot drag of his cock felt better with each passing second.
“Feels so good,” you said between moans. You were aware that other people could potentially hear you, so you tried your best to stay relatively quiet. However, that was getting harder and harder.
“You’re taking it so well,” Sebastian said as he began to thrust slightly faster. You could feel his breath against your neck. “You know, I wanted to do this to you the first time I showed you the Undercroft. I wanted to fuck you right up against the wall. I knew how good you’d feel around my cock. I knew that cunt would be so tight and wet.”
“You should have done it,” you sighed as he continued to pound into you. Every nerve ending in your entire body felt like it might explode at any minute.
His mouth latched onto your neck. You knew you’d wake up the next day with a large, purple mark, but you didn’t care. “You know what I want?” he whispered, “I want you to come on my cock. Turn around.”
He pulled out of you so you could flip over and get on your hands and knees. When he entered you once more it was just as shocking and satisfying as the first time, if not even more so. His hands gripped your hips as his hips slammed into yours. You were making quite a bit of noise, but your thoughts were too scattered to realize.
Sebastian’s hand slid down between your legs and began to massage your clit. His every movement was perfect. You felt yourself getting close embarrassingly fast. Your cunt tightened around him over and over as you approached the peak. “That’s it,” he said.
Without warning a wave of sensation ripped through you. You writhed and moaned while every muscle tensed. Sebastian groaned as your walls tightened. You could feel his cock throbbing with every thrust. “Do you want me to fill this little cunt?” he breathed.
“Yes. Fuck, please, Sebastian.” You could barely form a sentence, you were so dizzy with pleasure.
“You feel so good, so tight on my cock. So—” He came suddenly, shooting a huge, warm load into you. You felt his cock pulse for a moment as he relaxed. As soon as he pulled out, you realized just how much cum was inside you. It began to drip down your thigh instantly.
You sat up, beside Sebastian, and fixed your clothes as best you could. “That was…” he trailed off and let his head fall back against the couch.
“I know,” you smiled. “So, did I pay my debts in full?”
“Not if it means we get to do that again.” He shot you a lazy smirk.
Footsteps from somewhere behind you made you both turn around. You tensed as you saw Ominis standing by the doorway to the boy’s dormitory. “You could’ve at least had the decency to cast silencio,” he said.
You looked at Sebastian, who’s cheeks were pink. “Sorry, Ominis,” he said.
“I didn’t say I minded, just that some of the other students might have.” Ominous crossed his arms. “In fact, I would’ve preferred if you’d just come back to our room. You know I can disable that pesky charm.”
You and Sebastian looked at each other. Maybe next time would be a little sooner than you thought.