Disclaimer- I am not JK Rowling; I do not own any of her characters and I did not come up with the brilliant idea which is Harry Potter.

A/N- This is my first fanfiction on this account, and my first Harry Potter fanfiction, period. I have followed Snape/Harry mentor fics for years, however, and absolutely adore them, so I'm thrilled to be writing my own. This story is essentially going to be an alternate third year for Harry, going off of the idea that Snape was the one who taught Harry to produce a Patronus, and in the process, grew closer to him and discovered things about his home life. I have high hopes for this story, and hope everyone enjoys it!

Harry Potter slumped down in his chair, absent-mindedly chewing on the end of his quill. In the front of the Defense classroom, Professor Lupin paced back and forth, gesturing enthusiastically while lecturing on the origins of boggarts. The class had finished with the practical portion of their first lesson, which Harry had to admit, was more interesting and exciting than any other Defense class he'd attended at Hogwarts. Loads better than Quirrel's ramblings on the dangers of vampires. And Lockhart…well, Harry supposed anything was a step above Lockhart.

The effects of an actually engaging lesson were evident throughout the class. Even Ron, who normally slept thorough lectures, seemed to be listening attentively to Lupin. And Hermione was scribbling down notes with even more intensity than normal, Harry noted.

Slumping even further in his seat, Harry sighed heavily. Lupin was certainly different than any other professor Harry had encountered. He seemed relatable. Friendly, enthusiastic, and strangely enough for a professor, funny. Still, Harry couldn't help but feel a bit of resentment toward him. Everybody else in class had been encouraged to fight the boggart during the practical lesson. But when Harry had stepped up, excited and anxious to take his turn, Lupin had hurriedly pushed him away and defeated the boggart himself.

Harry frowned in memory. Hermione hadn't gotten to fight the boggart either, he reminded himself. However, she hadn't exactly been shoved aside. Picking at the edge of a piece of parchment, Harry lost himself in thought.

Maybe he hadn't been allowed to fight the boggart because Lupin considered him weak, or cowardly. Harry's gut clenched as he remembered the dementor incident on the train. He'd collapsed, even though nobody else in the compartment, or even the entire train, had done so. Professor Lupin had fought off the dementors while Harry had just lain there pathetically. Perhaps that was why Lupin wouldn't allow him to fight the boggart, Harry mused anxiously. Maybe Lupin had decided he was too weak to fight dark creatures since he couldn't even tolerate the presence of one.

At that moment, Lupin scanned the class and made fleeting, coincidental eye contact with Harry. Remembering his previous contemplations, Harry felt his face turn red. Hurriedly, he busied himself by pretending to take notes.

"…and that wraps up how boggarts came to reside in modern day Europe, as opposed to their original origins in ancient Egypt." Harry tuned into what Lupin was saying, realizing with a wince, that he'd missed the entire lecture.

"It seems our time together is nearly up," the Professor informed his class with a small smile, sitting down at his desk in a rather fatigued manner. "But I'll see you all again this Thursday. For homework, I'd like everyone to read the first chapter in the Defense textbook; it covers boggarts and hinkypunks, which we will be discussing next week. I'd advise you all to take notes," Lupin added with an amused grin. "There just may be a pop quiz in the future. You're dismissed."

Chatter broke out amongst the students as they began to pack up and disperse. Ron, who was sitting next to Harry, turned to him with a wide smile.

"Wasn't that wicked? I don't think we've ever had a lesson like it! I mean, I kicked that spider's arse! And when Neville imagined Snape in his Gran's dress-"

"Of course that's all you'd care about, Ronald," Hermione interrupted in a mock-haughty tone, plopping her book bag onto the boys' table. "It was more than an amusing lesson. It was absolutely fascinating! I mean, I read the Defense book already, but it didn't cover half of what Professor Lupin told us about boggarts. I wish I'd gotten the chance to fight it! Oh, I just hope the rest of the class will be this informative!"

Ron scratched the back of his neck uncomfortably. "I'm sure it will be, 'Mione," he muttered with a frown. "Doesn't mean we can't have some fun with it."

Harry smiled slightly, amused at his friends' bantering. He began packing up his bag as the two of them continued to bicker mildly. Suddenly, a new voice joined in the conversation.

"So, did you all enjoy the first lesson?"

Harry jerked his head up hurriedly, eyes wide. Professor Lupin stood next to Hermione and Ron, smiling gently. Nearly all the class had already left, with only a few stragglers still present.

Immediately, eyes bright with genuine enthusiasm, Hermione began to reminisce about how wonderful the lesson had been. Ron chimed in with a few off-hand comments, while Harry sat there awkwardly, mind still fixated on how Lupin had pushed him aside earlier. Watching the Professor closely, Harry startled when Lupin's curiously amber-colored eyes met his own.

"What about you, Harry?" Lupin addressed him kindly. "Did you enjoy the lesson?"

Face burning, Harry nodded rapidly as he grabbed his book bag and stood up in one fluid motion. "Yeah," he muttered, rubbing the back of his head. "It was real good."

Harry's comment sounded stupid even to himself. All he could think of was getting away from the room, and Lupin, as soon as possible. Turning to Ron and Hermione, who both looked at him questioningly, he clenched his teeth.

"We'd better go, or we'll be late to Potions."

With that, Harry spun around and walked as quickly as he could toward the classroom door. The back of his neck prickled uncomfortably as he listened to Hermione hurriedly apologize to Lupin. Exiting the room, Harry groaned lightly as he rounded the hallway corner and leaned against the stone wall. Stupid, he chided himself. If Lupin didn't think he was an idiot before, he certainly did now.

Suddenly, footsteps rushed up behind Harry, and in a moment, Ron and Hermione stood beside him.

"What was that, mate?" Ron questioned, adjusting his robes, which had gone askew during his sprint down the hall. "Potions doesn't start for another fifteen minutes, at least."

Harry tried his best to look nonchalant. "I…don't want to be late. You know how Snape gets in a foul mood when we're late."

Ron snorted. "Come on, it's Snape. Is he ever not in a foul mood?"

"I just don't want to be late, ok?"

"Really, Harry, you're being a right pain in the-"

Ron's comment was cut off with a sharp yelp of pain as Hermione elbowed him in the ribs. Rubbing his side, Ron scowled furiously at her.

"Honestly Ron," she huffed. "Can't you tell something's bothering Harry?" Turning toward Harry, Hermione gave him a half concerned, half exasperated look. "What's the matter?"

Harry groaned. Explaining his concerns to Hermione was the last thing he wanted to do. "Nothing's wrong, I swear," he said rather sharply. "Just drop it, Hermione."

Hermione's face fell, and for a moment, Harry felt a bit guilty for snapping at her. However, within seconds, Hermione's expression changed from hurt to haughty. With a loud 'humph!' of indignation, she jerked her head away. "Fine, be that way," she sighed. "I was only trying to help."

Embarrassed, Harry stared intently at his feet. The trio stood in awkward silence for a moment before Hermione glanced at her wristwatch.

"If we don't leave now, however, we will be late to potions."

With that, she turned away and flounced down the hall. Hurriedly, Ron and Harry trailed after her.

"I hate potions," Ron complained to Harry as they made their way down to the dungeons, his annoyance with the other boy already forgotten. "Especially the first lesson of the year. Snape always gives some sort of quiz. Like we should really be expected to memorize the entire bloody book over vacation. And I'll probably get a Dreadful on my summer assignment. Honestly, as if anyone could write four feet on the differences between healing balms and potions."

Pushing a lock of bushy hair aside, Hermione glared at Ron in mild annoyance. "Four feet isn't that bad, Ronald, especially considering how large your handwriting is. And you're not expected to memorize the text, but you should at least read it! I found time to read the entire book during my vacation!"

"Of course you did, 'Mione. Reading is all you do."

Suddenly, Harry stopped in the middle of the hallway, realization dawning. Heart pounding, he grabbed his book bag off his shoulder and hurriedly began to dig through it.

Hermione frowned. "Forget to do your summer assignment?"

Harry shook his head rapidly, continuing to rifle through his things. "No, I think I left my potions assignment in Lupin's class. I was finishing it up at the beginning of his lecture, and I packed up so hurriedly…."

"Snape's going to murder you, mate," Ron said, sounding nearly amused.

Harry dug for a moment more, then sighed and slung his bag back over his shoulder. "I'm doomed," he agreed without hesitation. Snape loathed missing work. And he loathed Harry. Bad combination; and Harry doubted Snape would listen to any sort of explanation.

Even Hermione, still irritated with Harry, and who normally would've chided him for his carelessness, seemed to understand the severity of the situation. "Think you can run and get it in time?" she questioned.

Harry bit his lip and glanced at his watch. "Probably not, but it's not like I have much of a choice. Maybe I can get a note from Lupin, or something."

Hermione nodded briskly. "We'd best head off though. Sorry we can't wait, but…"

Harry nodded. "Go on ahead—I'll hurry." With that, Harry turned around and began jogging down the hallway, heading back up towards the Defense classroom. If it had been any other essay he'd forgotten, he wouldn't have even bothered returning to Lupin's room with such little time left between classes. He'd have just explained what had happened to the appropriate professor and risked getting scolded a bit. Better than facing Lupin to retrieve it after the way he'd had left the Defense classroom. Now Lupin was probably going to consider Harry careless as well as cowardly.

Harry jogged up a staircase leading to the third floor, where the Defense classroom resided at. Still, he thought to himself, he had some sense of self preservation. Choosing between facing scorn from Lupin or Snape, he'd choose Lupin in a heartbeat, bad opinions and all. Panting slightly from his sprint up, Harry slowed his jogging as he reached the Defense classroom. The door was shut, and uncertain as to whether or not Lupin was even in his room, Harry hesitated to enter. Swallowing heavily, Harry reached up to knock, but before his hand could even touch the wooden door, a voice called out from within the room.

"Come right in!"

Jumping slightly in surprise, Harry wiped his palms on his trousers before pushing the door open. The classroom was empty except for Lupin, who was sitting at his desk doing some sort of paperwork.

"Hello Harry," Lupin addressed him, setting down his quill. "What can I do for you?"

Still hanging in the door frame, Harry quickly glanced towards the table he'd sat at during class, and felt his stomach drop when he saw his essay wasn't there.

"Err…well, I reckon I left my Potions essay in here," Harry began, shuffling his feet nervously. "But I could be wrong. Sorry. I didn't mean to forget it or anything, and I don't want to bother you. But if I don't find it, Snape will kill me."

Lupin smiled kindly. "Professor Snape, Harry. And you're no bother at all."

Harry shrugged awkwardly, not knowing how to respond to that.

"And luckily," Lupin continued, "I happened to find your essay while cleaning up after class." Shuffling through some items on his desk, Lupin held up Harry's essay with a triumphant grin. "It seems as though you won't have to face Professor Snape's famed wrath today."

Harry managed a crooked smile at that, and felt his nerves lessen slightly. Really, he thought to himself. Lupin seemed nice enough. Even if the Professor thought Harry was weak, shouldn't he be working to disprove that, instead of running out of classrooms like a coward? What kind of Gryffindor was he?

Feeling rather embarrassed with himself, Harry quickly walked up to Lupin's desk and accepted the offered parchment.

"Thanks," he murmured, shoving the essay into his bag.

"You're quite welcome," Lupin replied mildly. However, he studied Harry's face with an intensity that made Harry look downward to avoid his gaze.

"I'd best head off to Potions, sir," Harry said after a moment of heavy silence. "Thanks for finding my essay," he added with a hesitant grin. "You're right; I wouldn't want to face Professor Snape without it. He doesn't care for me much as is."

Lupin nodded slowly at this. "Of course, of course," he murmured, almost to himself. "Well, I'll see you again soon Harry. Don't forget the assignment for our next lesson."

"I won't, Professor," Harry promised. "Thanks again." Turning to leave the room, he hesitated for a moment, remembering his previous thoughts about the Professor. Now, his concerns seemed rather silly; Lupin didn't seem angry or disappointed in him in the least. Rather, the Professor acted friendly, and seemed eager to help. Frowning slightly, Harry paused at the door to the classroom, questions storming through his head.

Curiosity and confusion won over conflict. Working up his courage, Harry turned back around. "Professor Lupin," he spat out quickly, before he could change his mind. "Do you mind if I ask you a quick question?"

The Professor looked up from his papers rather sharply, but after a moment, smiled gently. "Not at all," he replied.

Harry swallowed thickly. "Well…I was just wondering…why you didn't let me fight the boggart in class today. I mean, I don't really care or anything, but everyone else got to, and I know I could have done it if you'd let me, and I don't mean to sound bratty or anything but I just thought maybe-"

"Harry," Lupin cut him off, his eyes surprised. "Calm down a moment."

Harry flushed, realizing he'd been rambling. "I just…I thought maybe you thought I couldn't do it or something. That I was too weak." Looking down at the floor, he avoided eye contact with the Professor.

Setting his quill down on his desk, Lupin sighed heavily. "I apologize if I gave you the wrong idea, Harry," he said gently. "I don't think you're weak at all—quite the contrary. I'm certain you could have fought the boggart off, but I didn't want the class in a panic if they saw Lord Voldemort suddenly appear."

Harry jerked his head up, eyes wide, as everything suddenly made sense. "Oh," he said softly. "I get it. I didn't even think of Voldemort though. I reckon my boggart would have been a dementor."

"Ah," replied Lupin, eyes widening with understanding. "I see. Dementors are indeed frightening creatures. After the incident with them on the Express, I can imagine they would be quite fearful to you."

Harry nodded rapidly, feeling as though a weight had been lifted off his shoulders. "Yeah, that's why I was confused when you wouldn't let me fight the boggart. I thought maybe because I couldn't stand the dementor on the train, you didn't want me to fight the boggart of it either."

Lupin closed his eyes. "I apologize, Harry. Giving you that idea was not my intention."

Opening his eyes, Lupin regarded Harry seriously. "And another thing, Harry. You should know that dementors are amongst the darkest of creatures in our world; they feed off of people's fears and unhappy memories. Because of this, those of us who have experienced and seen true horrors in the past are more affected than others. You are not weak, Harry. I promise you."

Harry swallowed harshly, remembering how hopeless he'd felt when the dementor was near him. How cold and frightened he'd been, with that woman's screams and pleas echoing through his head…

"Is…is there a way to fight off dementors, Professor?" Harry asked hesitantly. "I know you did on the train, when that one came into our compartment. Ron and Hermione told me. Do you think you could maybe teach me to fight them too?"

Lupin studied Harry intently, eyes filled with an emotion Harry couldn't quite place.

"I…don't pretend to be an expert at fighting dementors, Harry," Lupin answered weakly. "Quite the contrary, in fact."

"Please, Professor?" Harry pleaded. "I have to know how to fight them off, how to defend myself. I can't be affected like that again, I just…I can't." Harry looked down at the ground, blinking rapidly.

"Harry, fighting off a dementor…it's highly advanced magic," Lupin answered gently. "It's not something we normally teach at Hogwarts, let alone to a third year like yourself."

"I know," Harry replied. "But I have to try." Harry lifted his head up, looking Lupin directly in the eyes. "Please?"

Lupin gazed at Harry a moment longer before sighing heavily. "I'll talk with Dumbledore about it, Harry," he replied. "And see what he thinks; you would need the headmaster's permission, anyway, before learning such magic."

Harry grinned widely, unable to help himself. "Thank you sir!" he exclaimed, feeling nearly giddy with relief. He would learn to fight off the dementors, he promised himself. He wasn't weak.

Lupin smiled back. "You're quite welcome. Now, shall I write you a pass to Potions? I don't suppose Professor Snape would appreciate you arriving twenty minutes late to class without one."

Harry laughed, nodding happily. "I don't think he'd appreciate it at all, sir."

Remus Lupin stood in front of the gargoyle which guarded the Headmaster's office. "Sugar Quills," he addressed the gargoyle, who upon hearing the password, slid aside to reveal a set of spiral stairs. With a slight grimace, Remus began making his way up the staircase, dreading the conversation to come. He knew where this conversation would lead, and what revelations would result from it. But he had promised Harry. And he of all people could understand the desire to protect oneself against the despair the dementors brought.

Reaching the office door, Remus hesitated slightly before bringing his hand up to knock.

"Come in!" a voice called from within.

Swallowing harshly, Remus opened the door. Albus sat behind his desk, sipping a cup of tea.

"Ah, Remus!" he exclaimed happily. "Come sit down! Would you like anything to drink— tea, or perhaps pumpkin juice? How was your first day of classes? No problems, I take it?"

Smiling at the Headmaster's chattiness, Remus took the offered seat. "Nothing to drink, thank you," he replied. "And as for my classes, they all went very well. No problems, though there is something I'd like to discuss with you."

"Of course, my boy," the Headmaster replied, eyes twinkling, as he took another sip of tea.

Remus drummed his fingers on the desktop nervously. "Well, after class today, I had a discussion with Harry. He asked me if I'd teach him how to defend himself against dementors."

Albus' blue eyes turned serious. "Ah yes," he murmured, setting down his cup. "I heard about Harry's run-in with the dementors on the Express, the poor boy. I do wish the dementors' presence here at Hogwarts were unnecessary, but with the Ministry insisting…"

"Yes, of course," Remus replied reassuringly. "No one blames you, Albus. We all understand the necessity."

The Headmaster nodded, though his eyes remained solemn.

"I believe it's important that Harry learn to defend himself from the dementors, Albus," Remus continued. "Not because he's in danger from their presence here; I know you'd never allow that to occur. But with his history, with what he's experienced in his past, they affect him quite severely; enough so that his boggart is actually a dementor. I believe teaching him to produce a Patronus would greatly ease his tension."

"Yes, I quite agree," Albus replied with a sigh. "Of course. You have my permission to teach Harry."

A knot formed in Remus' gut. "That's the thing, Albus. I myself am unable to teach Harry to produce a Patronus."

Albus frowned slightly. "That does pose a slight problem," he remarked. "But I do understand. With your transformations and your recoveries from them, it would be quite difficult for you to take on extra lessons."

Remus clenched his fists. His condition was definitely cause enough to excuse him from these lessons, but he couldn't live with the guilt if he allowed Albus to believe that were the true reason.

"Actually, Albus, that's not the reason behind my unavailability." With a shaky breath, Remus continued. "I am unable to produce a Patronus."

The Headmaster glanced up from his tea sharply, looking about as startled as Remus had ever seen him. "What do you mean, Remus?" he questioned gently. "I understand you were the one who fought off the dementor on the Express."

Clenching his teeth, Remus sighed heavily. "I should rephrase. I am unable to produce a Patronus without great effort. On the Express, there was only one dementor, and I had the motivation to save Harry. It took a great deal out of me to even produce that Patronus, incorporeal as it was."

Dumbledore studied Remus, his eyes piercing. "I know in the past, Remus, you were quite adept at producing a Patronus. What has changed?"

It took all of Remus' strength to continue. "Since…since James and Lily died, and Sirius…well, since then, I've been unable to produce a Patronus."

"I'm so sorry for your pain, Remus," Albus murmured softly.

Remus cleared his throat harshly. "It's of little importance," he replied thickly. "The point of the matter is, I am unable to teach Harry, and I know how important it is to him to learn this. Is there any chance you could teach him, instead of me? Or know of someone who could?"

The twinkle reappeared in Dumbledore's eyes as he smiled at Remus. "Not to worry, my boy," he reassured him gently. "I know of just the person."

Hope everyone enjoyed the first chapter! Snape has yet to make his grand appearance, but he will in the next chapter- I promise!

Please, please review? They make my day, and provide great motivation to write faster. ;D