Disclaimer: This is a work of fan fiction using characters from the Harry Potter world, which is trademarked by J. K. Rowling. Though Liana Nevin is an original character of my own creation, Sirius Black is a character created and owned by J.K. Rowling, and I do not claim any ownership over him or the world of Harry Potter. The story I tell here about Sirius Black and Liana Nevin is my own invention, and it is not purported or believed to be part of J.K. Rowling's story canon. This story is for entertainment only and is not part of the official story line.

Hogwarts Battle of The Sexes

Hogwarts School of Witchcraft and Wizardry

1976

Liana Nevin wandered through the empty hallways of Hogwarts during this particularly gray winter day, wondering how she could entertain herself throughout the holiday break. She was among the few who remained on school grounds during the holidays, as she didn't get along with her adopted family back home and didn't have any close friends at school who ever invited her to their places either. She was an outcast, through and through, and this sat well with her. She didn't care for idle chat just to fill the time and preferred the company of her books and muggle records over trivial gossip of students and faculty.

As she wandered the hallways, she passed the Prefects' bathroom. She halted at the entrance and gazed at the massive doors. She had only ever heard of how lavish the Prefect's bathroom was in passing, imagining how lovely it must be to soak in a beautiful large pool of sparkling warm water, surrounded by bubbles and bath oils and all other sorts of luxurious things. She suddenly had a brilliant idea, and made her way to her room in the Slytherin house dungeons.

The Prefects' bathroom was notoriously difficult to get into unless you knew the password, which was reserved to house prefects, Quiddich captains and house head boys and girls. Though Liana carried none of those titles, she did have a very strong skill set of eavesdropping while making it look like she was deeply engrossed in her studies, overhearing many interesting (as well as not-so-interesting) things. One of those more interesting things was the password to the sumptuous private bath, which she never had the courage to use while the school was so crowded. On holiday, the school was practically empty, save for the few other students who preferred to stay away from their families as much as possible. The perfect opportunity to test the authenticity of the prefects' password.

She opened the door to her dormitory and pulled out her trunk from under her bed, kneeling beside it on the ground. She thumbed through her custom-made record collection, wanting to match the music perfectly to her first experience in the legendary bathroom. She selected a few records and put them in an enchanted book bag, along with the cumbersome record player, two or three of her favorite books, and a change of clean clothes. She closed up the small bag and slung it over her shoulder, walking quickly back to the fifth floor.

She looked up at the tall doors again, closed her eyes, crossed her fingers and said in a confident voice "Spotless". The huge doors swung open and she was drenched in a gorgeous warm light that glowed from within the room. She looked up and down the halls once more for signs of possible witnesses before stepping inside and closing the doors behind her. The bathroom was so much more than she had imagined. Gleaming marble counter tops with gilded taps fixed above opal shell-shaped sinks lined one side of the room. The far wall directly in front had an elaborate shelf which held countless bath products, towels and bathrobes of each house color underneath several stained glass windows of mermaids brushing their hair and flapping their tails about. The other side of the room was lined with private stalls and toilets. Right in the center of the opulent room was the famed Prefect bathtub, which looked much more like a small swimming pool with hundreds of taps to fill it with various soaps, foams, oils and such. And she had it all to herself, or so she thought...

What Liana didn't realize was that a fellow student had a similar idea that she did. This Gryffindor's name was Sirius Black, and he too was bored and looking for entertaining ways to pass the time during his time to himself through the holidays. Like Liana, he too overheard the password many months before. Though, unlike Liana, he had been frequenting the bathroom quite often since he had learned it, not really caring if anyone knew he had no business being there.

He had just finished soaking and was in the private stall getting dressed when Liana walked through the front doors. Sirius shrank back at the sound of the door opening, but seeing it was just some dumb Slytherin girl through the gap in the stall, he regained his composure quickly. He peered at her through the gap more closely, trying to come up with a name, but failing. He had seen her before, but she tended to keep to herself to where he had never learned her name. She was a year below him and pretty enough, but still a Slytherin, and that was enough for him to think less of her. Still, he kept watching her in secret as she situated her things on the counter across the room.

She pulled out the heavy record player and set it on the shiny marble surface. She then took out several records, carefully selecting one and setting it gently on the spindle. She placed the needle on the outer ridge of the record, and the room was suddenly filled with the sounds of Don't Fear The Reaper. Sirius was taken aback at the fact that this Slytherin girl enjoyed the same muggle music as much as he did. He watched her sway back and forth to the rhythm as she began unbuttoning her blouse, revealing the lacy black bra underneath. She slipped her skirt over her hips and kicked off her shoes to the beat, rocking her hips as she sang along to the song, using her wand as a faux microphone.

Sirius felt a rush of warmth in his pants as she undid her bra and saw her perky tits bounce as she flung it across the room like a slingshot. Liana stepped up to the edge of the sunken bathtub and pulled her panties off before stepping into the soapy water. She placed her wand at the edge of the tub, and slid deeper into the warm water so that she was just above knee deep in the middle of the pond-like bath. She bent down and reached into the water, pulling it up to her breasts, letting it roll down from her throat and drip off her perky nipples. She knelt down into the water, grabbing her tits as she sank.

Liana felt the warmth envelop her body and let out a long moan as she settled into the water. Sirius felt his cock swell slightly at the sound of her pleasure. She looked as if the weight of the world fell off her shoulders along with her restricting clothing, her face relaxed, framed by dark waves of her soft hair. He gazed at her smooth curves as she slipped her hand under the water and slid her finger between her wet lips. She ran her hand up and down her little pussy before settling her middle finger on her horny clit. A soft moan escaped her lips as she rubbed the throbbing flesh, slowly at first. She squeezed and twisted her nipple as she fucked her other hand below the surface, more and more feverishly.

Her moans were growing louder and louder, causing Sirius to grab onto his now very hard cock, pumping in time with her rhythm as he watched her intensely. He closed his eyes and imagined what her cunt felt like under the water, how swollen her lips must be, and what she might taste like. He couldn't help letting out a soft groan. His eyes snapped open as soon as the sound escaped him, causing Liana's moaning to stop completely. Her eyes were now wide with fear as she looked around the seemingly empty bathroom.

"Hello?" she called out in a small voice. "Is there someone there?" Her heart was racing with excitement and fear. She lifted her hand out of the water to brush the hair out of her face for a better look around. She started to make her way over to her wand when suddenly she saw movement out of the corner of her eye. There in front of her was a boy she knew as Sirius Black, pointing his wand at her from outside one of the stalls.

"Don't move. I won't hurt you, but if you make for that wand, you won't like the outcome." Sirius told her in a strong voice. She shrank back into the water to cover her naked body, eyes wide and locked on his powerful gaze. She saw his eyes wander down passed the surface she was hiding under, feeling herself blush a deep red as his dark eyes sparkled deviously.

"What's your name?" he demanded. His eyes were locked on hers again and had to look away shyly before answering.

"I... My name's Liana... I didn't know anyone else was... Please, let me get dressed. You can have the bathroom all to yourself." she answered, still unable to look him straight in the eye. Sirius looked at her again with the faintest of smirks on his lips. He pointed the wand at her again.

"Get up. Out of the water." he growled.

"But, I'm... My clothes are over there..." she looked over at the random articles of clothing scattered along the floor. Sirius looked at her and smirked wider this time.

"Oh, you won't be needing those. Stand up. Now." he said forcefully. Liana's face seemed to lose it's color as his words sank in, realizing how vulnerable she was, unarmed and naked. She slowly stood up from the tub, water and soap suds dripping down her silky skin. She wrapped her arms around herself in an attempt to cover her soaking body.

Sirius felt his cock press against his pants as he drank in the sight before him. He walked to the edge of the tub and stepped into the water. She looked on in horror as this shirtless young man pointing a wand at her drew closer. She started to step backward, but stopped when he clicked his tongue at her as an adult would to a naughty child.

"No, no, no. You stay right where you are, Liana." He reached out and grabbed her hand. He pulled it down between her thighs as she let out a gasp of air and winced at his touch. "I seem to have interrupted you. It would be rude of me not to let you finish..."

Liana looked into his eyes, utterly confused. "Finish? I... I can't!" she exclaimed. With his middle finger on hers, he pushed them both against her clit, causing her to moan softly. She pressed her body harder onto both their fingers, riding them for a split second before her eyes widened in shock, angry at her body for betraying her. She shrank back. He grabbed her shoulder with his wand hand and brought her closer, keeping his hand firm against hers between her legs.

She shut her eyes as he began to push her hand up and down her dripping clit, ashamed of feeling herself getting wetter and wetter by the second. Sirius pressed his body against hers as she rocked back and forth on their hands, crying out in some combination of pleasure and shame.

He pushed his face into the nape of her neck, inhaling her sweet scent as she writhed around, coming so close. So very close.

He withdrew his hand from her thighs suddenly before she came. Her eyes snapped open as he did, pleadingly. He grinned at her expression, knowing how badly she wanted him to continue.

"Naughty little Slytherin girl... You want more, don't you?" He quipped. She was confused again. Her mouth was pouting ever so slightly, driving Sirius over the edge. He flicked his wand toward her before she could regain her composure. "Coercere!"

Ropes of light shot out of thin air, wrapping themselves around Liana's wrists and ankles and pulling her taut. She cried out as she was stretched out in front of him.

"Please! Don't!" she begged, quivering against the ropes that bound her. Sirius drew close to Liana, who was hopelessly trying to free herself, and grabbed a fistful of her hair and pulled her head back roughly. She yelped in surprise, eyes pleading silently as Sirius took his free hand and gently grabbed her throat and slowly traced his fingers down her chest, across her stomach and finally stopped between her legs.

He ran a finger down her swollen clit and grinned when she whimpered in guilty pleasure. Liana couldn't stop herself from feeling immense pleasure by being touched by a hand other than her own, and a part of her was furious at her body's deceit in this. She moaned loudly as he slid a finger deep in her sopping cunt. He grazed her neck with his lips and teeth, feeling her shudder at his touch.

"Please don't what?" he whispered in her ear, still pumping her pussy with his finger. She arched her back against the restraints, grinding her hips further onto his hand.

"Please... Don't stop..." she moaned in his ear. He tugged her head back again and kissed her full on the mouth, his dick growing harder as she slipped her tongue across his lips. He pulled her head back and looked her straight in the eye, but she shyly looked away again. He slipped another finger inside her, flicking her throbbing clit with his thumb. She began to writhe more and more against his hand as she came closer and closer. He roughly moved her head toward his own.

"Look at me." he told her. "Look at me and don't you dare look away." She opened her eyes and locked on his, feeling her orgasm coming closer and closer. She began to close her eyes, but he jerked her head and they locked eyes again.

Sirius could see the pleasure she was trying so desperately to contain, and a smirk pulled at the corner of his mouth. Her moans grew as the ecstasy within boiled over. Liana couldn't hold back any more. Her body quaked as she came, a waterfall gushing from her tight pussy. Sirius lifted his thoroughly soaked fingers up to her lips, which she instinctively took into her mouth, licking the juices greedily from them.

He kissed her again, tasting her lingering flavor on her tongue before pushing her down into the water on her knees, unzipping his pants to free his big cock. The look on her face was that of a young girl who had never seen a raging erection before that moment, but that subsided quickly as she parted her pouting lips.

He pushed his cock toward her open mouth, and she timidly wrapped her lips around it. Liana had never seen one before that day, let alone put one in her mouth. She started to pump his shaft with her lips, feeling it pulse beneath her tongue. Sirius groaned loudly and gently pulled her head back and forth by the hair he still clutched in his fist.

Liana felt her pussy getting wet again and moaned with his dick still in her mouth. Sirius pulled her face back off his cock and lifted her up out of the water to kiss her wanton lips. She gave in completely and melted into his mouth with her own. As he kissed her, he pulled off his pants completely, tossing them into the water clumsily. His hands entangled themselves in her hair as his tongue danced along with hers between their lips. He flicked his wand at her again, this time releasing her binds, then tossed the wand to the edge of the tub next to hers. They kissed passionately before he turned her around and they both sank into the warm water.

"You're a strange sort of girl, aren't you?" Sirius murmured in her ear from behind her, hands snaking across her skin to squeeze her firm tits. Liana cooed at his touch, lost in ecstasy and lust. She could feel his rock hard dick between her pert ass cheeks, so close to her wet slit. She arched her back, pressing her ass against his hips.

He couldn't hold back any longer, and shoved his cock inside her. She cried out in pleasure and pain, feeling him break through her. He thrust even harder, her pussy tightening as he went deeper and deeper. Her moans turned into howls as he fucked her, warm soapy water splashing between their glistening bodies.

Sirius could feel the walls of her cunt closing tighter and tighter as she reached her climax and felt his own grow like a wildfire. He felt the gush between her creamy thighs as she came, her body tense, yelling out in ecstasy.

He grabbed Liana's hips tightly, forcing her back and forth on his cock roughly. He couldn't take much more, holding her quivering body against his. With a loud groan, he pulled his dick out of her soaking pussy and shot a thick, white stream of cum all over her curvy ass, rubbing the throbbing rod against her sullied cheeks.

Liana felt her body go limp and collapsed in the water. She lifted her body slightly, still trying to grasp what she had just experienced. She looked up at Sirius with glossy eyes as he pulled his pants out of the bath and walked to the edge of the tub. He bent to grab his wand casually and muttered a charm which instantly dried them out. Her mind was foggy, still recovering from the intense sensation of her frenzied bath.

"Wait. Where are you going?" She managed to ask as he pulled his shirt over his head. He looked over to her and smirked. It was a smug look that made her want to punch his teeth out, had she had the strength and energy. His eyes shined down on her deviously.

"I've got plans. Lovely to meet you, Laura." He answered as he shouldered his bag and walked to the doors. Liana felt her face grow flush with rage. Every muscle in her body was tense as she scrambled to get out of the water, but Sirius had already walked out, leaving her seething as she stared incredulously around the now empty room.

"It's LIANA, you bloody prick!" She shouted at the closed doors. She got out of the tub, huffing in outrage as she picked up her clothing and pulled them on roughly.

Liana looked at her disheveled reflection in the mirror. Her hair was a mess and her clothing rumpled. Even in her state of disarray, she felt a smile pull at the corner of her lips. Though she was an odd sort of Slytherin girl who didn't lust for power as much as others, she was a Slytherin for a reason and not to be trifled with.

She would get back at that damn Gryffindor if it was the last thing she ever did. She would make Sirius Black pay in full for his actions. And she planned on laughing the entire time.

The End.