Severus Snape woke groggily the next morning. He'd had the most horrible dream ever and was currently suffering the worst headache imaginable. Something about a diary and finding out he might be Harry Potter's -

He jerked upright and the throbbing in his skull increased to an intensity the man wouldn't have thought possible. Had he suspected any amount would cause him such repulsive nighttime delusions, Snape would have never allowed even a drop of alcohol to so much as pass his lips.

Rising to his feet, Snape stalked to the bathroom and jerked open the medicine cabinet. Snarling silently, he grabbed up a Headache Draught and downed it. He was out of his special formula for hangovers, which meant he would have a mild headache all day, regardless. What was worse, he had Potter in class that morning.

The Potions Master scowled. It was going to be a foul day.

- - -

Harry felt the hair along the back of his neck stand on end. He had hoped that the glares – or rather, one continuous glare – that Snape sent his way at breakfast had been mostly in his head. Now, there was no doubt the man was furious at him.

"What'd you do?" Ron whispered as he took out his class supplies. Harry's stomach attempted to sink into his toes.

"I don't know," he replied hoarsely, setting his cauldron on its stand. Never did Double Potions seem so incredibly long.

After a terse lecture which evoked more questions than answers, Snape flicked his wand towards the blackboard and the potion they were to make appeared in the professor's spidery scrawl. Harry couldn't decide if it was more legible in ink or chalk.

"Harry, are you sure you didn't do anything you shouldn't have?" Hermione asked quietly as they made their way to student supply closet for the ingredients they needed.

"Hermione!" he exclaimed. "Yes, I'm sure. I haven't done anything all year." The girl gave him a dubious look, but dropped the subject when Ron nudged her elbow, offering Harry his support. They returned to their tables and set to work.

His teacher's temper, despite its unknown source, did have one positive effect: it sharpened Harry's focus. Contrary to what the potions professor believed, Harry really did have some natural skill for potions. Granted, he couldn't write an essay to save his life. Furthermore, the ridicule heaped upon him since his first class had dampened his enthusiasm for the subject considerably, so said gift went unnoticed and unexplored.

The cause of most of his mistakes during class lay in the constant uncertainty of whether Snape would be in his usual ill-temper or in an even worse one. Today, however, the man was already angry with him, for whatever reason, guaranteeing that scathing personal abuse would eventually come his way. Though, not a pleasant prospect in the least, this left Harry able to ply his attention to the task at hand, with good results.

"Potter!" Snape snapped from right behind him just as he was adding ground gurdyroot to his cauldron. Miraculously, Harry's hand remained steady.

"Sir?" he asked, looking back at the professor over his shoulder, hand still poised over his assignment. His apparent composure served only to irritate the man towering over him.

Snape peered down at the concoction in the cauldron. Potter was only a few steps from completing what looked would be a perfect potion. "What, in Merlin's name, do you call that?" he sneered. Before the boy could respond, he vanished the fluid away and snapped, "Start over."

Closing his mouth with an audible snap, Harry clenched his jaw. Glaring after the teacher for a moment, he made his way to the supply closet to a chorus of titters from the Slytherins. Spiteful ol' git, he thought venomously, I didn't even do anything...

Harry continued to seethe as he returned to his work station. There was just no getting around it. He hated the man.

- - -

He'd heard of torment such as this. If memory served, the victim was strapped down as a single droplet of water was dripped onto his forehead at undetermined intervals. In this manner, the poor soul was slowly driven out of his mind.

Snape's torture was very similar, indeed, despite its lack of physical stimulation. All day long, he'd found little respite. He'd be minding his own business when his headache would flare and he'd remember a line from the journal. Every flash of dark hair was Potter. A carefree laugh summoned Lily's voice; a seventh-year's pale, slender hands were also hers.

And now, he stood in his quarters, unseeing gaze fixed upon Lily's diary still laying open on the floor of his study. He could see her teeth worrying her lip, hear the rasp of her palms pressed together. She was folding her arms defensively – no, protectively, wrapping them securely around her stomach. Hurt, tear-bright eyes regarded him – "I'm sorry, Sev..." – echoed in the face of his childhood enemy. But that wasn't right, either. Apart from the messy black hair, did Lily's child truly look like James Potter at all? Or had he, like everyone else, merely been seeing what he'd expected to see?

No! No.

Snape shook his head, backing out of the study without what he'd come to retrieve. This was madness. Nonsense. He had a class – classes, all full of ignorant children who might manage to kill themselves without his supervision. Yet, still the memories plagued him. A glimpse of the brat scowling over something at lunch nearly sent him over the edge.

"I hope Harry looks like his father, just a bit."

Severus stormed into a lavatory, needing to be alone, if only for a minute. "OUT!" he snapped at the two dawdling boys he found within. The idiots nearly tripped over themselves in their haste to evacuate and the Potions Master turned his scowl towards the mirror.

"It's absolutely absurd!" he snarled at his pacing reflection. "What were you thinking? It's not a wonder you've suffered such a nauseating nightmare. You never consume that much! It's not -" Severus gagged at the mere thought. "It's not possible – not in the least. I have excellent deductive reasoning and mathematical skills, if there were any chance... no. Not a chance. It's not possible – I was DECEIVED!"

As his voice rose in a fierce shout, the door – which had started to open – was jerked shut again and retreating footsteps echoed down the hall. Staring at the door a moment, Severus turned his black gaze back to the mirror above the sink.

"It's not possible," he whispered stubbornly. And he would prove it. He would read Lily's diary again, leaving the liqueur cabinet closed so as to avoid any thoughtless imbibing like the night before. Only then could he return to his numb routine. There was no chance . Severus Snape was a father to nobody – least of all to the bloody Boy-Who-Lived.

- - -

Harry ran a hand through his hair as he sat down for lunch, then frowned minutely. Ulgh... Surreptitiously, he wiped his hand on his trouser leg. He really should have washed his hair that morning, but he had overslept, meaning he'd had no time for a full shower. It wouldn't have been so bad if he hadn't had Potions that day. Nothing like cauldron fumes to make his hair oily, fast. He shot glances at Hermione's and Ron's hair, but both looked the same as always. He concluded that it must only be him.

Deciding that he'd shower right after his last class of the day, he suddenly recalled that he had detention. A scowl took his features as he thought about it. So, he wasn't the best potions student – his assignment had at least been closer to accurate than Neville's. Snape obviously vanished his first attempt so that he could give Harry detention when he didn't finish. Greasy git...

Harry looked up as Snape stormed out of the Hall. Good, he thought, won't have to look at him. Hermione was discussing an Arithmancy assignment with one of her classmates, so Harry tuned in to the Quidditch discussion with Ron and Seamus. A few minutes later, Neville joined them, having stopped off to talk to Professor Sprout instead of going straight to lunch.

"You alright, mate?" Ron asked him, glancing up from his plate. The boy looked paler than usual.

"Y-yeah," Neville nodded shakily. "I-I'm fine." Ron exchanged a dubious expression with Harry while Hermione frowned.

"If you say so..." Conversation gradually picked up again, the topic turning to their Defense Against the Dark Arts class that afternoon. Professor Lupin was beginning a new topic, which meant they would be encountering a new creature that day – and that was almost always something to look forward to.

- - -

Lupin watched with barely restrained amusement as Neville Longbottom's boggart was suddenly dressed in his grandmother's clothing. The image of Severus Snape in a dark green dress, fox fur about his neck, with a large red purse in his hand and vulture perched upon his head was one that would remain with him for a long time. Oh, yes. A very long, pleasant time. How very fortunate that he had managed to find the creature.

One by one the students took their turn, chanting riddikulus, their fears turning comical before their eyes. When it was Harry's turn, Remus couldn't help but look on with increased interest. This child, who in several ways puzzled him, what would he fear?

The boy stepped forward to face the boggart, looking a bit eager and nervous all at once. As the creature turned towards him, a cruel smile twisted its features as a pale, snake-like face began to emerge, causing many in the class to gasp in surprise and terror. Just as rapidly, though, a different form was taken by the shapeshifter, revealing a round, purple-faced man with mean, beady eyes. The next instant, it was morphing again, and Remus thought he caught a glimpse of scales and white-blond hair before it finally settled into a seemingly harmless apparition. It looked like... a locked cupboard.

Harry had started at the sight of Uncle Vernon. He hadn't ever really considered the man an object of fear. Before he could think any more on the matter, however, the boggart was changing again, starting to turn into the basilisk, then – after a flash of something furry – Lucius Malfoy.

When at last it stopped, he was staring at his cupboard. For ten years, he'd been forced to live in the cramped, spider-infested little space, and even now it was the very place where everything that tied him to the wizarding world was locked away each summer. The painful clenching of his heart constricted Harry's chest as an overwhelming emotion swept over him, his outstretched arm starting to shake. It wasn't quite fear... no, it was worse than that. It was -

"Riddikulus!"

The shapeshifter turned into a shiny, silver orb which promptly deflated like a popped balloon. A moment later, it was banished back to the wardrobe in which it had taken residence.

"That's it for today. Everyone write a foot and a half on boggarts for next class. Dismissed."

He was gasping in air, now. He hadn't even realized he had stopped breathing. Somewhere around him was the sound of shuffling feet and indistinct murmuring. Just as everything fell quiet, a hand gripped his shoulder and Harry found himself looking up into a pair of gentle brown eyes.

"Alright, Harry?" Lupin asked.

"Yes, sir," Harry answered a bit hoarsely.

The professor frowned at this, then pressed, "Are you sure?" The boy nodded. "Harry, about that man and the locked door -"

"I don't know why the boggart became either of them, sir."

"You don't?"

"No, sir," Harry insisted. He didn't want his teacher to know about how much his relatives hated him or how every summer was an unending, lonely hell which left him feeling as uncertain and insecure as he had been first year. Dumbledore had made it clear that he had to go back, so speaking about it would do nothing. Besides, what did it matter that his aunt and uncle completely despised him? That even the meager kindness of regular meals was too much of an imposition for them? It didn't, so Harry said nothing. It was too embarrassing, anyhow.

"Harry..." Lupin began.

"I don't, honest!" Harry cried out, pulling away from the man. "Professor, please – I don't want to talk about it!"

"Alright," the man said, holding his hands up placatingly. "You don't have to tell me. But, Harry, if you ever need to talk..."

"There's nothing to talk about, professor."

"Okay. Alright. But if there is, you know where to find me."

Harry studied his face almost suspiciously. "Yes, sir," he replied. "Thank you." And with that, he left the room without a backwards glance.

- - -

Snape scowled at the messy head of hair bent over the textbook. The brat hadn't said so much as a word after he'd been set to work. He had duly informed him that after he finished his potion from class, he was to scrub cauldrons for the rest of the evening, but Potter hadn't even looked defiant.

Frowning to himself, the Potions Master returned to the papers he was grading. Deplorable. He didn't even know why he bothered with most of the mindless idiots. Just as he was halfway through a rather scathing remark about a second-year's lack of a functioning brain, Potter came to stand before his desk.

"Yes?" he snapped, looking up into the boy's face. His eyes seemed a bit... vacant. So, the little monster was sulking, was he? How very Gryffindor. No doubt, he fancied that he was taking unjust treatment with the patience of a sainted martyr. All the more evidence in his favor. He'd never behaved in such a fashion.

"I'm finished, sir," Potter answered, holding out a vial full of potion. It was the exact shade that it should be. Snape did not comment on this, however.

"Clean up your mess, then get to work scrubbing the cauldrons," he said disinterestedly, setting the vial on his desk and returning to his own task.

"Yes, sir," came the soft reply.

Minutes later, Snape glanced up as Potter scrubbed obediently. Was he not going to give even the slightest protest? The boy seemed oddly... resigned. The Potions Master wasn't used to such compliance from the child. Surely, Potter was smart enough to realize that this punishment wasn't entirely deserved? Even Snape knew he had acted spitefully in vanishing the boy's assignment.

"Potter." Green eyes raised to meet his, a spark of... well, something in their depths. "Put everything away and get out of here. I have things to tend to and I do not wish to return to check on you."

The boy stared at him, then nodded. "Yes, sir."

Snape leaned back in his chair as the room fell silent a few minutes later. He concluded that something was clearly bothering the boy – the Brat-Who-Plagued-Him-at-Every-Turn was never so compliant. But even if that were so, did he even care?

No, he sniffed silently, putting away his grading, definitely not.

- - -

Later that night, Snape found himself in the door to his study staring at the open book on the floor. Facing the source of his confusion left him feeling uncertain. Did he really want to undergo the torture of reading Lily's words, again? Reluctantly, he crossed the floor and lifted the book in his hands, eyes falling upon the open page.

"Nov. 14, '79

"He hates me. Sev absolutely hates me."

His eyes squeezed shut of their own volition. He'd forgotten about this entry. Opening his eyes once more, he continued reading.

"I knew he had this side to him – a side that was darker, that could look down on others. But he also has a gentle side – one that finds humor in life, that knows how to smile. A side that I thought loved me.

"It's not fair! I can't help who my parents are! So what if they're both Muggles? It doesn't make me any less of a witch, didn't keep me from being top of our class. I thought Sev was above such narrow-minded bigotry, but I guess he isn't.

"By god, I'm so confused! I even ended up talking to James Potter, of all people. I don't know why I did. I just felt so lost. He kept his word, though – he didn't judge me, or speak ill of Sev, even though they never got along.

"I'm in love with a Death Eater! Even if he still felt the same for me, I could never be with him. Voldemort would never allow him to love a muggleborn. What do I do?

"My palms are sore. I can't even think about that without crying. How many times has Sev berated me for rubbing them, then put one of his clever potions on them to make them feel better? It hurts SO MUCH. He hates me... And I don't know how I'll ever feel happy again."

Severus could almost hear the hurt in her voice, see the anguish in her eyes. So, Lily hadn't run to James after he'd rejected her. Talked to him, yes, but if it had been anything more, she would had written it in the same tide of emotion that had made the entry so disjointed. He had hurt her. More than he had imagined. He lay the diary on his desk and slowly sank down into his chair. Painstakingly, he put his skewed deductive reasoning aside and truly applied his prided mathematical skills for the first time.

Lily's child had been born at the end of July. Full gestation was forty weeks. Assuming that Potter had, in fact, been carried full term, that meant that conception would have been sometime in... His breath came out in a sudden rush, images of pale flesh and passionate green eyes flickering through his mind. October. They had spent more time together than apart that month.

Severus pinched the bridge of his nose, drawing in a shaky breath as he finally allowed himself to accept the truth: Harry Potter could be his son.