Hey guys! I'm going to be honest here – I actually just wanted to write a smut piece with James as a professor and Lily as his student, but then I couldn't stop thinking about HOW this would authentically work, and what their motivation would be, and before you know it, I had already written 35k words (not finished yet). So yes, it starts off rather tame, but I'm planning on it getting downright filthy before the end... so you have been warned!

I plan on updating at least weekly.

Disclaimer: JK Rowling owns Harry Potter. Art work by the extremely talented Viktoria Ridzel (Instagram: viria94)

Her emerald eyes glinted mischievously as she leaned down over his chest, her fingers splayed teasingly over his warm pectoral muscles. She looked as though she was glowing from the inside out, part Veela if he had to guess. Her deep red hair cascaded over her shoulder and tickled the delicate skin of his cheek. "All right there, Professor?" she asked, her gorgeous face a mere centimeters from his.

He felt his lips crack into a smile as his hands moved up her milky thighs of their own accord. He still wasn't quite used to the title, but he'd roll with it.

"Professor?" Her velvety voice was laced with concern now. James was confused. What had just gone wrong? Nothing was wrong. This is bloody heaven.

"Professor?"

James Potter snapped out of it, his eyes opening to the harsh reality of where he was: the Transfiguration classroom. It wasn't the first time he'd fallen asleep there… it was, however, the first time he'd fallen asleep and woken up as the teacher.

"Uh— yes?" he stammered, his eyes focusing on the 3rd year in front of him. This was going to be a long school year…

"I heard it's James Potter," said Dorcas Meadowes, Lily's best friend.

Lily rolled her eyes, really over this bullshit. "For fuck's sake, will you let it go." Lily's friends had been on her case about her little schoolgirl crush for years now. It didn't even matter that they were currently 7th years and James had left Hogwarts three years ago. "That was ages ago."

"And yet… you're still not over it," Dorcas said with a sly wink. "No, but really, I did hear it was him."

"Ha ha," was Lily's sarcastic reply. There was no way on earth that James Potter, thee James Potter, was teaching during Professor McGonagall's sabbatical. No fucking way.

"Okay… find out for yourself," Dorcas said walking towards the class with her hands up in mock defense.

McGonagall had announced quite suddenly the week prior that she was off to Korea to study ancient shape shifters. Lily thought it sounded more like a vacation than anything, but she supposed the teacher deserved some time off. McGonagall had been fighting against Voldemort and his Death Eaters for who knows how long and they had finally been vanquished. Lily still couldn't believe it. It had been eight years since she had found out she was a witch and nearly just as long that she'd known that her kind — Muggle-borns — were being hunted by the worst of them. Then this summer, all of a sudden, a baby had done Voldemort in. Poof. Like magic. His followers had dispersed overnight and all her bullies and tormenters now roamed the halls, wand in hand, looking lost for purpose. If they hadn't made her life a living hell, Lily might have felt bad for them… Yeah right, not in a billion years.

The girls rounded the corner into the classroom to find a spot with the rest of the Gryffindors. Ah shit, where's my quill? is the last thought Lily had right before being poked, rather harshly she might add, in the ribs. "What Dorc-" Then she saw what: James Potter, wearing black slacks and a grey knit sweater, was lounging against McGonagall's desk. His arms were crossed, but he gave her a lazy smile as their eyes met over the heads of her classmates. She tried to keep her face neutral, but a "Whaaaaat…" still escaped her lips.

"I TOLD you," Dorcas said, gently pulling Lily by the arm, somehow knowing she'd stay rooted to the spot otherwise.

"Did you? This can't be real." Lily could feel a blush spreading across her cheeks. This was a bit of a disaster really. She'd imagined running into James later, when she was perhaps in her 20s, as a successful potions master. He, a renowned Auror, had come to her for help with his new case. He'd see how much she'd grown, how wise she was now, and just — I don't know — fall in love. This was not how she'd pictured their reunion — with pumpkin juice breath and barely combed hair.

"You look fine," Dorcas whispered in her ear, seemingly reading her thoughts.

Lily kept her head down and unpacked her things on her desk.

"Good morning class," James announced, a whole lot more confidently than he currently felt. "As you know, Professor McGonagall is gone for the rest of the school year, so I will be filling in for her."

"Aren't you a bit young to teach?" Zaire Zabini asked haughtily. Lily scoffed when she saw her former best friend, Severus Snape, sneering sitting besides him. If looks could kill, James didn't stand a chance.

James swung one leg over the other, still leaning against his desk. Looking like a damn GQ ad. "I suppose I am young. But if I'm old enough to fight Death Eaters, I'm sure I'm old enough to teach some spells."

Lily scanned the room. It looked as though she wasn't the only girl blushing… the girls from Hufflepuff, Ravenclaw, hell, even one Slytherin, all had stupid grins on their faces. This is not happening. This year is too important to have a dumb crush. This year is N.E.W.T.s!

"Prove it," Snape snarled. Lily could tell James' comment about Death Eaters had gotten under his skin. After all, it was Snape's affinity for the Dark Arts that had ultimately driven a wedge in their friendship.

James rolled his eye and pushed off the desk. "If only to get you guys to listen up." There was an audible collective gasp as James' arms lengthened to the ground as hooves and his untidy black hair elongated to majestic antlers. James had just transformed into a magnificent stag.

"Bloody brilliant," Georgina, a Hufflepuff squealed as she animately clapped her hands. Lily had to agree; she remembered McGonagall doing just that to wow all of them first year. (Albeit a seven foot tall stag was a little more impressive than a tabby cat.) If he wanted to prove he was a worthy Transfiguration teacher, the class had gotten the message loud and clear.

The stag tilted his prongs to the board, took a leap, then became James once more. "Now, if my introduction has been quite sufficient, Professor McGonagall has left me a list of topics we need to cover before your end-of-the-year exams, and I'd assume you may want to get started rather than harping on about how wildly good I am at the subject." Lily didn't have to see his eyes to know that James had made that comment at Snape's expense. Snape had always hated Potter for what he'd gripe on for hours were his "privileges" and how the upperclassman got everything handed to him with zero talent. Lily had always just let him ramble and nodded, not wanting to fight with her friend about something so trivial. It hadn't been until 4th year that she'd finally started forming her own opinion about the messy-haired Quidditch captain and Head Boy… Course, at that point, he'd become a bit of a Hogwarts celebrity.

"So, please pair up, and if you'll open to page 216, you'll see instructions on how to transform your parter's noses."

James removed his glasses and splashed water on his face in the comfort of his living quarters. It amazed him that he'd lived in the castle for seven years and never really wondered where the teachers actually lived. Sure, McGonagall had on many occasions had to come out in her dressing robe to reprimand the Marauders for one late-night prank or another, but he'd never stopped and thought about where she went afterwards.

Now look at him, sleeping in his own luxury flat. The ceilings were high and his windows looked out towards the Quidditch pitch. James was sure an enlargement spell was in play, because there was not this much room in the castle for all the professors chambers to be so large.

James let himself fall into his king bed, reminiscing about his first day. The 1st through 3rd years had been easy enough. Some of them still seemed to be learning how to hold their wands, so a few tricks here and there were likely enough to keep them entertained. However, everyone 4th year and above remembered him. He supposed the 4th years had only witnessed him as a Head Boy — when he had his shit together a bit more — but the rest remembered what a giant pranking prat he'd been. James groaned. It would be a bit tougher to earn the respect of students if they could vividly recall him hexing all the ghosts to have red eyes and fangs on Halloween… although — as he'd adamantly pointed out then — wasn't the whole point of Halloween to be scared shitless? He tried brushing this reasoning aside. He'd have to be enforcing the rules now, not thinking of more and more creative ways to break them. James rubbed his eyes. Sirius was right. This was a terrible idea.

"Sooo?" Dorcas pushed, sitting with Beth Van Steen (their other friend) in front of Lily in the Gryffindor common room.

"Sooo what?" Lily said nonchalantly, pushing her hair back as she pretended to read over her Charms essay.

Dorcas rolled her eyes. "Oh shove it. The only bloke you've ever fancied, the only one, is back, and you don't know what my 'so' means?" Beth nodded in agreement.

Lily grinned despite herself. "So… yeah. Okay, I'm a little bit excited," she admitted, "but he's our professor." She annunciated every syllable of the word.

Beth smiled. "So what?"

"Soo," Lily continued, already getting peeved with the word, "that's that."

Dorcas made a face. "Okay killjoy, I'm not saying we should plan how to get you two alone so you can finally express your long-seated desires but—" she turned to look at Beth, "wait, actually, why the hell not?"

Beth giggled. "Yes! This is a sign Lily!"

"A sign?!" Lily exclaimed. "Yeah, a sign that it never would and never will happen."

"How do you figure?" Dorcas said, narrowing her eyes at her.

"Because…" Lily was really flustered now. "He's. Our. Professor."

"Oh come on, Lily! He's only 20 and your 17. That's hardly illegal." Beth reasoned, accepting Dorcas' high five.

"You two are incorrigible."

"Nah…" Dorcas said. "We just have a normal teenage libido that we're really hoping will rub off on you one of these days."

Lily threw her homework at her friend. Then quickly snatched it back realizing it wasn't quite done.

"All right. Well, I have to go finish the Prefects schedule with Benjy and you know I have to have my wits about me around that one… so I'll be off."

Dorcas groaned. "Good luck."

"Thanks," Lily sighed.

The next week passed quickly enough, with James becoming used to his new position while Lily tried to get accustomed to seeing him in it. She found herself spending a little extra time in the morning charming her hair just right and applying her makeup a little less carelessly.

"Miss Evans, may I have a word?" Lily's heart skipped a beat upon hearing that phrase at the end of Transfiguration class Friday night. She could hear Dorcas squeal, but her mind was racing, never actually having gotten into trouble before. What's this about? Her nose transformation hadn't been that bad. At least her transformation had matched Dorcas' dark skin color, unlike Benjy Fenwick's hot pink one, or the completely disfiguring one Snape had given his partner. The poor lad had had to go to the hospital wing to remedy the damage and Lily had a sneaking suspicion that Snape had done it on purpose.

As the rest of the class filed out, Lily timidly walked towards James' desk where he was tidying up some papers. "You wanted to see me, Professor?"

James looked at her over his glasses, smiling. "Don't worry, you're not in any trouble," he said correctly reading her visage. "It's Lily right?"

Lily's heart sank. He doesn't even remember your name. If he had noticed her disappointment, he didn't let on. "Yeah, Lily. Like the flower." You dumbass. He KNOWS what LILLIES are.

James smile stretched farther. "Well Lily-like-the-flower, can I ask you a question?"

Oh no. Lily's head spun. He's on to you. He's gonna ask what the hell your problem is and point out that it's so inappropriate to drool over a professor like this. "Yes, sir."

James chuckled, his tongue slipping out to wet his lips as his eyes twinkled. He leaned over his desk towards her and Lily was overcome with the fact that they had never actually stood this close before. Well, not since he's been back. "How am I doing?" he whispered.

"W— what?" Lily stammered a little too quickly.

James motioned around the room. "Teaching. How am I doing? To be honest, I feel like a bit of a tosser most of the time I'm up here." His hand went through his hair nervously — a habit Lily remembered all too well.

"Oh no!" Lily replied. "No, you're doing great! I love the practicality of it. So many of our classes focus so much on the theory, it's always great when we can be hands on in class and you're really good at that…" she trailed off, not liking where her dirty gutter mind was going.

James flashed the most dazzling smile and she felt herself melting. "All right, well, if it's good enough for the Head Girl, that's probably a good sign. Thank you."

He knows you're Head Girl, but he forgot your name. Sigh. She'd take what she could get of course. She decided to tease him a little bit. "I mean, you're no McGonagall… but you'll do."

James smirked. Lily internally let out a sigh of relief knowing she hadn't gone too far. "Well, no one can top Minnie."

"Minnie?" Lily's eyebrows furrowed in confusion. "Maybe I shouldn't ask…?" James grinned wickedly at her. She felt like she was on a roll. "You going to the game tomorrow, Professor?"

James had cleared his desk now. "Oh, who's playing?"

"Gryffindor versus Slytherin."

James' eyebrows shot up his forehead. "You know I have to see that. We have anyone good on our team still?"

And just like that, Lily felt like the barrier between student and teacher had fallen and James was just another Gryffindor ready to kick some snake tail. "Well, we have me now," Lily admitted sheepishly.

"Huh, no kidding… what do you play?" James asked, genuinely curious.

"Keeper."

James pushed away the thought of Sirius saying something completely demented like, 'If she's a Keeper… she's a keeper.' "When'd you start?"

"5th year…" Lily said innocently.

James racked his brain. "Did you ever try out earlier? I could have used a good Keeper you know. Ours bloody sucked. Got distracted by any shiny ray of light." James huffed thinking about Mundungus.

Lily smiled; she remembered him. "I was too scared to try out sooner I guess."

"Scared?" James asked puzzled. "Why? You don't strike me as the fearful type."

You. "Well, Professor, I'm sure you've noticed I'm kinda skinny. It's terrifying having people who try to kill you in the halls then have free rein to pelt Bludgers at you on the pitch."

She had meant it as a joke, but she saw his face darken. "Of course." James flicked his wand erasing the lesson plan from the board. "Make sure to get some rest, Miss Evans. I expect a win tomorrow." Then he strode towards the back door.

"Yes, sir," Lily replied to her shoes, wondering if she'd done something wrong. She walked to the Great Hall for dinner, ready to answer Dorcas and Beth's inevitable incessant questions.

No shit, she had every reason to be terrified. James mentally kicked himself for asking her such a stupid question. He remembered how crazy the halls had been at times with Death Eater wannabes getting emboldened by Voldemort's steady rise to power.

Muggle-borns across the school had been targeted left and right, and Lily had been one of them. The pretty little redhead with the almond eyes. James sighed. Of course he remembered her and her name. In his effort to sound like he wasn't picking favorites, he'd pretended as though he hadn't been sure of it, but the pain that flashed behind her eyes wasn't worth it. Of course he remembered the girl he'd gotten a black eye for, having defended her from Avery after he tried hexing her between periods. He'd told his mates it was because he was the Head Boy, and it was the right thing to do… which it was… but he'd always kept a bit of an eye out for the witch with the crimson hair and the green eyes. Course to admit that he fancied a 4th year would have been social suicide… and his friends would never have let it go.

Now here she was. Still skinny, but she'd grown into herself more. James tried not to focus on any body part in particular. She'd gone from pretty to drop dead gorgeous. James groaned, hitting the back of his head against his door. These were not thoughts very becoming of a professor.

'What bloke becomes a professor at 20?!' Sirius' indignant line bounced around his head. 'You just stopped being a teenager yourself. Bet Dumbledore must be mad desperate, mate.' James finally agreed with his best friend's assessment.

He decided he'd skip dinner tonight and just raid the kitchen's later. James was at least grateful the Marauders and him had so thoroughly mapped out the school while they'd been there, never quite getting enough of Hogwarts' mysteries… his classmates' lack of absolute, drop-everything and go, intrigue of the castle BAFFLED him.

Students'. His students' lack of intrigue.