This is a story of evolution, taking place from Harry's fifth to seventh years at Hogwarts. The passage of time is rather fluid, and I've played around with ages a little bit, so that Harry is 18 during his seventh year. Snarry. As ever, let me know what you think. Loving thanks to girlwithsixarms.

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The halls were empty – the entire castle was deserted. The corridors were almost pitch black, the murk only punctuated at intervals by dim torches inlaid into the walls. Weren't the lamps usually brighter? Hogwarts really would benefit by upgrading to some electricity, Harry reflected, as he stumbled over an uneven stone, wrapped in his invisibility cloak; he'd been sent by Hermione and Ron to raid the Restricted Section because Snape'd been acting suspicious lately. Even more suspicious than normal, and Harry was sure he was up to something. Hermione had overheard him mention something about this spell, or curse, called The Dormientis Prodare. Although Hermione had been combing the Library for information for the past few nights, she'd been unsuccessful, and Harry had been elected to explore the Restricted Section. So Harry was, grudgingly, trudging down the hallways, tripping over the rough floor, and trying to avoid wayward cats that would summon errant caretakers and get him into trouble.

Oh shit! Harry heard someone coming, rapid footsteps heading toward him, and he immediately flattened himself against the wall. Harry peered into the darkness at the black figure looming toward him. Only Snape had footsteps that sounded like that. Very even, very quick. Since when had Harry noticed that Snape had distinctive footsteps?! Harry shrugged at himself and waited for Snape to pass by him.

But the tip of one of his black boots brushed against the bottom edge of Harry's invisibility cloak. It was just Harry's lousy luck that Snape's boot caught on it, just a little, just enough.

Snape turned and peered through the gloom and Harry inched sideways against the wall, but Snape thrust his great greasy hand out, grabbed the invisibility cloak, and yanked. Hard. And despite his attempts to squirm away, remain hidden, do something, he found himself staring into the burning, hateful black eyes of one Severus Snape.

When the Potions Master spoke, his hushed voice was calm, but Harry could hear undercurrents of loathing, like Snape wanted to be hissing instead of whispering.

"A little snake in lion's clothing. What brings him out of his den so late, patrolling the halls of Hogwarts? Especially with this little gem." Snape drew his hands across the invisibility cloak. "Something like this would be priceless in the Wizarding market, but would be invaluable for me."

Harry glared back at the bastard. "It's mine and you can't have it!"

"On the contrary, Potter, if I deem this as dangerous for a student, I may confiscate it for as long as I wish. Or I could deliver it to the Headmaster and see what he would make of his Prize Pupil, Savior of Wizardkind, meandering the halls of Hogwarts after curfew."

Harry didn't blink as he fearlessly met the glower of the Potions Master.

"Ah," Snape continued, his lips flitting with the curves of a smirk. "The headmaster actually gifted you with this precious cloak. But it appears you haven't been using it wisely as he first requested."

Harry spluttered as Snape turned on his heel, taking his invisibility cloak with him. "WHAT?!"

Snape looked back over his shoulder and there was a pause in his otherwise even steps. "Legilimency, Potter. Another thing to research in the Restricted Section. And one hundred and fifty points from Gryffindor. Get back to your dormitory."

Bastard. How was he supposed to get his cloak back?

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The halls were empty – the entire castle was deserted. Even the grey granite stones somehow seemed more despondent than usual. Harry marveled at how that was possible. As far as he knew, stones had no emotion, but it figured that Hogwarts stones would care more than other rocks about the goings-on of the world. The sky was dark, threatening rain, two days before Christmas. But Harry was, thankfully, not back at the Dursleys. Instead, he got to train with Snape and Dumbledore through winter break. Which wasn't a whole lot better than being with the Dursleys, with Snape always calling him things like a swollen lump with a head full of flobberworm ooze, or a vainglorious narcissistic egotist with a developing messiah complex, but Dumbledore was supportive when they discussed spells and curses, and at least he got enough to eat. Ron and Hermione were, with Harry's seemingly eager blessing, visiting their families for the holidays. He wished they'd stayed, but Dumbledore was enthusiastic about them returning home during break and Harry didn't particularly want to stir up any problems.

On the other hand, the intense dueling sessions between him and Snape made him want to rip down everything in the vicinity of the Potions Master, including the blasted man himself. Except if he did that, Harry had the sneaking suspicion that Dumbledore wouldn't be too pleased. And Harry would have to land at least a couple of curses on Snape in order to liquify him, which hadn't happened in almost two weeks of intense dueling.

Even with his frequent chats with Dumbledore about Voldemort, magic theory, and life, Harry just couldn't win. No matter how many times he tried, Snape managed to dodge, parry, shield, or return every single spell he fired.

Earlier that week, Harry had let off about ten different curses with varying levels of pain, right on top of each other. A jelly-legs, and a Confundo, and one that made all your hair fall out, and another that made you retch for hours. But Snape avoided them all. Not a single one managed to graze even the long black robe that twirled intimidatingly around the Potions Master as he fought back.

Perhaps, Harry had mused, if he'd had a cloak that swirled like Snape's, he'd be a more successful duelist. Then again, it would probably just get in his way, and he would do something embarrassing like trip over it and break his nose, which wouldn't help at all.

And if he couldn't land any spells on Snape, how the hell was he supposed to do any better against Voldemort? Especially if Voldemort attacked with Legilimency, too. Snape had started introducing that in their practices, but Harry was still garbage at Occlumency, so there wasn't much he could do except end up exceedingly pissed after Snape dredged up yet another humiliating memory. All this training certainly wasn't helping his confidence any.

Only once had he hit successfully hit Snape with any sort of spell.

"What if," Harry had gasped out after Snape had torched him with a particularly tricky curse, "I don't actually have to duel him at all?"

"What if, Potter," Snape ground out as he advanced on Harry like a panther, "the Dark Lord gives you no respite. What if, Potter," here Snape raised his wand, "the Dark Lord has taken your wand and you have no means of Priori Incantatem. What if, Potter" Snape snarled, "the Dark Lord just kills you! Dorm-"

Harry summoned up his last dregs of energy. "Expelliarmus!"

Simple, a first-year attack, childish, yet still Snape's wand soared into Harry's outstretched hand as Harry collapsed onto the ground. But Harry didn't have it long. With a pulling motion from the Potions Master, the ebony wand was yanked out of Harry's hand and disappeared into billowing black robes. Damn Snape's wandless magic.

Snape turned and swept out through the classroom door, leaving Harry on the wooden floor to lick his wounds and gather his strength. "Well done, Harry."

Exhausted, bruised, and aching, Harry didn't realize that Snape had called him by his given name until he fell asleep that night. Although it did occur to him that if he had his invisibility cloak back, it might be harder for Snape to hit him with all these painful spells.

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The halls were empty – the entire castle was deserted. During the day, the castle was warm and smelled of the fast-approaching spring. Sometimes, when walking between classes, and often right after lunch, turning the corners, there were gusts of delicious spring air. Students were baffled, and no one could decide if it was natural, or the castle's own doing.

But evening had settled over Hogwarts, and something was loose on the grounds. Two of Hagrid's new Wormplesnoots. As big as dragons, but as "Tame as Fluffy!" according to the Care of Magical Creatures professor himself. They were currently taking massive chunks out of the lake's giant squid. All the students had been sequestered in the dormitories, awaiting word from the tense teachers who were currently meeting in the staff room, deliberating over a suitable course of action. Snape, true to form, was skipping out. He'd gone to get Harry. As practice, they were going to duel the Wormplesnoots.

Snape poked his head past a grumpy Fat Lady into the almost bursting Gryffindor dormitory. "I need Harry!" he called into the jammed room, in his most commanding voice.

There was sudden, absolute silence, except for a loquacious first-year in the corner who had yet to discover the full wrath of Professor Snape. She was quickly elbowed by an anxious second-year, but he jotted a mental note to put The Fear into her during her next Potions class. And then he quickly glanced around for Harry, who was by the couches near the fire with Ron and Hermione, as usual. Hermione swiveled around to face the door, a puzzled look on her face before she leaned over to Harry and muttered something in his ear. Harry shrugged before he pushed his way through the crowd of students and came out through the portrait.

In a distinctly non-Wizarding hooded sweatshirt and pair of black jeans, he walked beside Snape in his billowing black robes.

"You're going to go stun two Wormplesnoots, just to prove to yourself that you can."

Harry looked up in astonishment at his professor. "Are you NUTS?"

Snape glared down at him and Harry withered. A little.

"Are you nuts, sir!?"

Snape let a slight smirk touch the edges of his lips as they headed for the main castle doors. "Perhaps. You're still going to do it." The sound of their footsteps echoed through the hall, companionable silence settling over them. Yet Harry couldn't help but feel he was going to his doom.

"You know," Harry ventured, "maybe if I had my invisibility cloak back, I would be more successful with this whole defeating-Wormplesnoots thing."

"You're going to be successful regardless. Your invisibility cloak would only assist you in your as-yet unsuccessful death wish."

Harry harumphed. He really did want his cloak back.

Despite his skepticism, Harry gamely attempted to subdue the Wormplesnoots. He tried Stupefy about a hundred times. It just made them angry, although they did start chasing him around for a while instead of toying with the giant squid. But being inches from the ends of their claws made him wish they'd go back and kill the local wildlife. And Snape was no help at all – he just sat on the steps to the castle and watched, leaving Harry to feel like he was stuck in a bad sitcom.

Snape did get riled up, though, when Luna came out. Somehow she'd gotten out of the Ravenclaw common room, eager to see the Wormplesnoots. "See!" Luna called excitedly to Harry while she pointed to the giant creatures. "I told everyone they were real years ago, but no one believed me!" Harry had moved from Stupefy to Somnolus, and was about to try Wingardium Leviosa in desperation, and Luna was telling him they were real. Of course they were real! And now was really not the time. Snape, fortunately, was trying to get her back inside to the Ravenclaw dorms.

"Ms. Lovegood, it is imperative that you return with all due haste to the protection of Hogwarts. This is a volatile, unpredictable situation, and–"

Luna, oblivious, tried to help Harry. "You should really just tickle their bellies! They really like that! I read about it in one of my dad's articles in The Quibbler a couple of months ago!"

Harry had little faith in the methods of The Quibbler, but his repeated Somnolus seemed to be having an effect. The Wormplesnoots's movements were getting more and more lethargic until, finally, they lay down, creating rather huge craters in the grass where they collapsed. Luna applauded excitedly, only making Harry feel more like he was an actor in some disaster of a farce.

Finally, the other professors rushed onto the lawn, ensconced in darkness. McGonagall was passionately voicing her fury, but Harry noticed a slight twinkle in Dumbledore's eye. And Snape seemed almost proud.

Harry was sent back to bed with a measly twenty points for Gryffindor for "finally letting a tiny modicum of useful information seep through that agonizingly impenetrable skull after years of painstaking toil on the parts of your betters." It was only twenty points, but it was twenty points granted by Snape!

He toppled into bed, exhausted and happy, having bypassed all the questions in the common room except Hermione's subdued and simple, "Did he call you 'Harry' again?"

He answered with an easy smile as he headed upstairs. 'Harry' just couldn't be spat quite the way 'Potter' always was.

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The halls were empty – the entire castle was deserted. Or at least mostly deserted. Harry was skipping out of the welcoming feast, where Dumbledore was probably reciting his customary three or four words before letting the Sorting commence. Harry was relaxing by the fire in the common room, enjoying the incredibly rare silence, only broken by the occasional pop of a log in the fireplace.

He'd stayed over during the summer to train with Severus, and his Occlumency had improved tremendously. Surprisingly, when the Potions Master wasn't stressed by classes, other treacherous Slytherins, and "vapid neophytes always discovering new ways to explode cauldrons," he could almost be decent. Harry strongly suspected that Dumbledore had shared words with Severus, but while he was still prickly, he'd stopped trying to provoke Harry into casting Unforgivables, and he'd even stopped lambasting his dad and Sirius.

It was weird the first time Harry called Snape 'Severus.' It was at the end of an incredibly intense, three-hour training session, and Harry was lying, exhausted, on the cold wooden floor of the classroom in the Slytherin dungeons. Harry was trying to fall asleep, but Severus had nudged him with a heavy booted foot, telling him to get up and get something to eat. But all Harry did was roll over, swear, and mumble inarticulately, "Go 'way, Sev'rus." Expecting a biting comment about Harry's lack of due respect owed to his betters, Harry was relieved when none came and he was just left on the floor to recover. From then on, Harry tried to slip it into his sessions sporadically, just to see if he'd get a rise from him. He either didn't notice, or didn't care, and Harry'd gotten rather used to it.

However, despite his few dueling sessions with Dumbledore, for "variety's sake," Harry couldn't ever quite work up the courage to call him 'Albus.' While Severus's reflexes were quicker, and both teachers had a vast repertoire of spells, Dumbledore used curses Harry had never seen before. Apparently, as Severus had explained after one of many dueling lessons, there were certain classes of spells, more than just those classified as Dark or Light. The spells taught at Hogwarts were Latinate, but there were American and Eastern spells, too. Dumbledore had a soft spot for the Eastern ones, which were, as Harry experienced, distinctly vicious. He was getting particularly tired at being on the receiving end of this one that made him feel like he was being pushed through a cheese grater the wrong way (whichever way that was).

But after all this training, he did discover that he found himself on his arse less and less, and he knew he was hitting his teachers with more spells than he had when he'd begun.

And two days ago, Severus had told Harry about this spell that he and Dumbledore had created. Dormientes Prodare. They'd used an idea they found in an ancient Mayan ritual that the tribes would perform as a way to heal the terminally ill. But it wouldn't really heal them, it just sent them away. Severus and Dumbledore decided it might be the solution to eliminating the Dark Lord, as Avada Kedavra didn't work. Harry couldn't figure out how this crazy old ritual applied at all to the current situation and, after all, they couldn't test to make sure it worked, or anything. But Severus had just smiled wryly and said, "You'll just have to trust that we know what we're doing."

Suddenly, Harry heard the Fat Lady creak open, interrupting his musings, and looked up from the fire. It was Hermione, skipping out of the end of the Feast. She'd brought up a bunch of deserts on a purloined plate. He grinned at her as she came over and sat close to him on the couch while he reached for a piece of dense chocolate cake.

"Are you and Ron..." He started, before he tried the cake.

Hermione grinned. "Yes, finally. I think Fred and George may knocked some sense into him over the summer."

Harry snorted. "Sure took him long enough! There's been this thing between you two since forever!"

Hermione's grin grew wider. "I wonder what the twins told him!"

"Maybe something like 'So, Ron, has Hermione shown you how to properly use your magic wand, yet? Because you know she's so good at magic.'"

Hermione giggled before she collected herself. "That is so crass," she grinned, "but whatever they did, it worked!" She paused for a moment. "You know, you sent a couple of letters to the Burrow, but… Was your summer really okay?"

"Yeah," he nodded. "Surprisingly so. Much better than at the Dursleys. Severus's really not the awful greasy git we always thought. He can actually be really decent. And I've started dueling with Dumbledore! You know there are these amazing spells we never learn about because the Ministry's worried we won't be able to pronounce them correctly so–"

"The Eastern and South African ones, especially!"

As usual, Hermione's knowledge vastly surpassed Harry's. But sometimes she didn't tell him everything she knew. She kept her surprise at hearing Harry use the professor's first name quiet.

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The halls were empty – the entire castle was deserted. Severus had discovered at the last Death Eater meeting that Voldemort was planning to attack Harry as soon as the wards on Privet Drive fell and Harry turned 18, so even Harry was gone. Surrounded by nearly all the Order members, he waited anxiously inside the house, nervously jiggling his leg, hoping that the Order's carefully-plotted scheme would work. The Dursleys had temporarily left, albeit grudgingly, following the advice of Dumbledore, and now everyone had nothing to do but sit back and wait.

It started with a steady thud. Thud. Thud. Thud. Almost like water dripping, but quite a bit more insistent. Thud. Thud. Thud. It made Severus tense where he sat beside Harry. Thud. Thud. Thud. Which made Harry tense. Thud. Thud. Which made Severus reach over to graze Harry's hand with his. Thud. Thud. Which made Harry even tenser. Thud. Thud. Thud. But in a different way. Thud. Thud. Were they getting louder, or was Harry just imagining things? Thud. Thud. Thud. No, those were all the same. Thud. Thud. Thud. They were definitely getting louder, because that last one was – Thud! Thud! Oh Merlin. Thud! Thud! Thud! Harry readied his wand, preparing to attack. THUD!

After that, the thuds grew into full-fledged cracks as the house began to fill with Death Eaters. There were two behind the couch, and one was crouching in the center of the living room, and Severus's arm was wrapped around Harry, tugging him toward the wall and out of the crossfire. Bellatrix had just unleashed a hellfire of curses at Tonks, who was trying to incapacitate two positively boulderlike Death Eaters who must have been Crabbe and Goyle senior. Everywhere there were explosions and shrieking and curses and grunts – people falling and collapsing and disaster, and Severus was unleashing a torrent of spells at everyone around as he dragged Harry to the wall – some hit their targets and some went awry, but Harry couldn't for the life of him figure out why they weren't being liquefied as they stood, frozen, against the wall, until he reached his wand, ready to shriek an Unforgivable at that bastard Pettigrew who was aiming at Lupin and felt it! There it was, cool against the back of his hand. Severus must have covered them with the invisibility cloak. That's why no one was attacking them.

And Severus was talking to him. Trying, softly and insistently, to get him to calm down, to look away from the fighting, to listen. Harry blinked, dazed.

"You need to stay here and remain still." Severus's chocolate eyes bore into his soul, it seemed. "Don't come out, no matter what! And don't do anything rash." Harry, appalled and desperately worried, yelled at Severus to stop whatever he was thinking because – but Severus cast a Disillusionment Charm on himself and then ducked out from under the invisibility cloak to stand in front of Harry, protecting him from notice and any errant curses.

Surveying the room from behind Severus's broad shoulders, Harry tried to spot the Order members. Tonks was still there, dueling Macnair, and Molly and Arthur were helping each other fight off Lucius, but he couldn't see Remus. Was that him, in the kitchen? No, but –

A huge voice rang out, hissing, dry, awful. Curses still flew, green, red, blindingly yellow flashes blasted in zinging lines through the air, there wasn't even a pause in the battle. But it had everyone's attention. And it was splittingly clear. "The boy!" It grated, louder than everything else, in a high squeal. "Where is the boy!?" And suddenly Harry could see Voldemort standing on the other side of the room, wrapped in a seemingly impenetrable bubble, and Harry knew it would stay up until Voldemort tried to cast something. Harry also knew that Severus was going to hate him for this.

Harry stepped out from behind the Potions Master and yanked his invisibility cloak off.

"What the hell do you think you're doing?!" Severus yelled at him, in a panic.

"You wretched traitor!" Voldemort hissed. "You could have had such success, such power, such absolute command, but instead you've elected to become lackey to him!" Voldemort's lipless mouth sneered. "Your one blessing is that you won't have to live very long under those hideous circumstances."

"You bloody bastard!" Harry ranted, as he stalked across the room. "You coward! Come out from behind that shield, you miserable freak! Come out and do something! Severus is a thousand times more noble than you could ever be, you vile, disgusting worm."

Voldemort sneered and raised his wand. "Avada Kedavra."

"Dormientes Prodare!" A jet of deep blue light shot from Harry's wand to meet Voldemort's blinding green. Harry prayed that Priori Incantatem wouldn't fail him. He really didn't want to die today, and–

But it was failing, and Voldemort's green jet was making its way toward Harry, decimating Harry's blast of blue and Harry bent all his will on it, trying desperately to make it retreat toward its caster, but the green glow barely slowed down. Shit.

"Dormientes Prodare!" Harry heard Severus shout, as if from a great distance, although Harry saw him standing right beside him.

And then Voldemort split his attention, between Harry's curse and Severus's. Lucius jumped between Voldemort and Severus, and then Harry's jet shot right to Voldemort's heart, knocking him backward so that he slid across the pockmarked wooden floor into the wall.

Harry looked around, exhausted, trying to see what was happening. Things were deadlocked. Tonks's wand was pointed at Narcissa, who in turn was pointing hers at Bill, who had his hand tracked onto Crabbe. Crabbe himself had Molly in a chokehold, with her wand pushed into Avery's back, who looked like he'd had a rough round of Immobilicorpus. Countless others were frozen in astonishment or paralyzed from various curses. And everyone capable was afraid to move. Arthur Weasley's Adam's apple bobbed.

Then the front door squeaked open, the one Vernon was always yelling at Harry to oil, but no matter how much grease he added, it always sounded the same. A familiar redhead peeked his head around the oak, astonishment written across his features. He sauntered in, followed by his double.

Fred looked around in mock disappointment. "Harry, darling, you're having such a wondrous party, and we weren't invited?"

"You and all your friends were so loud, we couldn't help but hear. Did you really think you could pull all this off without us finding out?" George added with a sorrowful smile.

"You know," Fred finished with a shrug, "you could have just told us if you didn't want us to come."

Ron, Hermione, and Neville followed this little speech.

"But you didn't really think we'd miss all the fun, did you?" Ron and Hermione smirked.

Neville had hatred written across his whole body.

And the fighting resumed.

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The halls were empty – the entire castle was deserted. Well, Harry couldn't actually tell, because from the look of things, he was lying in the infirmary with Severus tucked into a nearby bed. But there were so many bouquets of carnations, roses, lilies, along with stuff that looked like it was going to try to eat him, that Harry suspected he might just be in one of the greenhouses. There were even a few potted trees off to the side, one so big that it brushed against the ceiling. Harry peered at it, trying to get it to come into focus. Was it a lime tree? Are there even lime trees?

"Don't even bother," Severus's deep voice informed. "I don't know why anyone would ever think you needed a lemon tree. Perhaps they thought that now you've successfully defeated the Dark Lord, you'd take to marketing lemonade." Severus looked around. "Although it appears that others suspected you'd consider vinification and ornithology." Severus eyed something in the tree. Harry shuddered. Harry had no idea what ornithology or vinification was, but both sounded bad. His head hurting, he leaned into the welcoming pillows with a rather loud sigh.

"Indeed, Harry," Severus commiserated as he plunged back into sleep, but not before he felt Severus's warm hand ghost over his forehead.

"Ah!" Severus awoke from a nightmare with a cry. He'd been tied and bound, and Voldemort had been torturing Harry in the worst way. Severus climbed, trembling, out of bed, over to Harry's. He knew it was silly, but he just needed to make sure that everything was okay, because it should be, but Severus had the nagging sensation that things were very, very wrong.

Harry was quaking under the infirmary blanket, little cries occasionally escaping his parched lips.

"Harry," Severus began quietly, soothing a hand down his cheek. "Harry, you're safe. The Dark Lord is gone, he…"

Harry's eyes eased open, almost overflowing with tears. He pulled himself up and reached to hug Severus. "It was… Everyone was gone… And I…" Harry's tears were muffled in Severus's chest, but when he pulled back and stared up into Severus's eyes, it was no effort for them to come even closer. Severus leaned down, and Harry pushed himself up, and his warm lips met Severus's, and his hand came around the taller man's shoulders, pulling him down toward the infirmary bed. Severus followed Harry down so they were both sitting on the bed as Harry opened his mouth and –

God, Severus was demanding, and reassuring, and not at all calming. Harry was not going to forget this and go back to sleep anytime soon, of that he was sure. Although, when Severus did that with his tongue, and gently tugged at his lower lip with his teeth, Harry was sure of little else except that he wanted more. Probably a lot more.

Harry pulled away, breathless, and he gasped for a moment, his forehead leaning on Severus's shoulder, long fingers carding through his disheveled hair.

After a few minutes, while Harry tried to collect himself both from the blistering kiss and from his traumatic dream, Harry disentangled himself from Severus's embrace and gave him an exhausted smile.

"I need to go back to sleep, I think," Harry told him, subdued.

Severus nodded, brushing his hands through Harry's hair one last time before he summoned a small blue vial. "Drink."

Harry took it, skeptically. "What –"

"Just Dreamless Sleep."

The black head nodded in understanding as Harry raised the glass to his lips. Their eyes met and Harry started to speak, but Severus cut him off. "Sleep now."

"Yeah, sure," Harry muttered before he drank and curled up on his side, exhausted. Severus pulled the blankets around him before he settled back into his own lumpy infirmary bed, still wide awake, still thinking.