Disclaimer: This is a work of fan fiction using characters from the Harry Potter world. No, I do not own Harry Potter or any of the other characters, surprising though that may be. JK Rowling owns the characters – I'm simply expanding on what she provides.

Summary: Harry is given a diary by Dumbledore and, when he writes in it, he receives an unexpected response. His correspondent learns of Harry's less-than-suitable living conditions and an unlikely bond is formed. Abused!Harry, DrugAddict!Harry.

Warnings: Swearing, drug abuse, reference to child abuse, reference to sexual abuse/rape.

Harry felt a little safer, now that he was in less pain. The last potion Snape had made for him worked, at least somewhat. It was incredibly addictive and did terrible things to his depression. But it was a necessary evil for now, until they figured something else out.

At least now he could eat and sleep and study with some semblance of normalcy. Harry had been taking it for almost ten days and was quite impressed by how well it was managing his pain.

He was currently taking a quarter of a vial every evening before bed. Apparently it was quite likely to become less effective the longer he continued to take it for. Snape had told him that they would have to monitor the pain and increase the dosage if it became ineffective.

They were calling it the scar potion. It had a strange earthy flavour of freshly cut grass with a rather pleasant minty after taste. Not nearly as bad as some of the other concoctions he'd consumed.

He was sleeping a lot better than usual and it dulled the pain to a barely noticeable throb. This was a vast improvement and meant that he was awake and aware enough to attend classes and improve his grades once again.

However, the side effects were extensive and Harry knew he couldn't continue to take it long term. He wasn't even sure if he should be taking it short term. The Slytherin had warned him not to show the scar potion to anyone, and not to mention he was taking such a potion.

It made him instantly sleepy, which is why he was taking it in the evenings just before bed. The drowsiness was not so strong as to cause him to be unable to stay awake if he really wanted to fight it. But it certainly impaired his ability to focus and he wasn't sure he could cast spells reliably immediately after consuming it.

It also took his appetite away even more than usual, if at all possible. He was rarely able to stomach any breakfast and could generally only manage a light lunch. He was eating as much as he could at the evening meal to make up for slim pickings during the day.

Whenever he had "detention" with Snape, he was generally encouraged to consume a light supper before taking his dose of the scar potion – any additional food he could stomach at any time was apparently a good thing at this point.

The worst side effect cause by the potion was that his depression was absolutely raging. The dark magic in the potion made his dark moods bleaker and more frequent. He was countering this by keeping as busy and distracted as possible. But, sometimes, the darkness was a heavy cloak threatening to suffocate him.

It also muted his pain in such a way that his senses were a little dulled. When he trained with Snape in the evenings his reflexes were slower and his ability to read magic as a spell came towards him was seriously inhibited.

Harry figured that, if he could fight half-way decent while under the influence of the potion, he might stand half a chance when he stopped taking it and was in complete control of his mind and his body once again.

It certainly wasn't perfect, but it was necessary, for now. It was better than wandering around in a haze of agony, anyway.

"Ah, I know what this one is. It won't help us. Move on to the next one." Severus waved one hand without looking up from the notes in front of him. His silky baritone was tinged with impatience.

Harry nodded and turned the page carefully, smoothing the paper before attempting to translate the next potion.

They were slowly working through the parseltongue book. It was painstaking work. The Gryffindor was unused to reading the snake language, which was not well phrased for written prose, and translating between that and English was incredibly challenging.

He would read each word aloud in parseltongue – the Slytherin had now become well accustomed to hearing Harry hiss darkly – and then attempt to repeat it in English. More often than not, however, he would repeat it a few more times in low hisses before he managed the translation. Snape would patiently shake his head at each wrong attempt and then quickly scribble down any English that Harry managed.

The pages seemed to hold lists of ingredients for potions. Some had measurements, but many did not. There were no titles and no recipes. So, it was the potions master's job to figure out what each potion did, based solely on the list and order of ingredients. No mean feat.

The younger wizard looked over at his tall professor, a curious gleam in his emerald eyes. They sat comfortably in armchairs in the man's dungeon quarters. It was late at night and they each held a steaming mug of tea. Harry nibbled at a small plate of sweet biscuits between attempts.

They had been spending a few evenings each week translating the book for the last few weeks now, and they were finally beginning to make some progress. Harry's translations were becoming more fluent and Severus was now able to identify some ingredients that were cryptically described when there was no direct translation. They were beginning to better understand the writer.

Of course, neither wizard had a clue as to whether or not there would be anything helpful in the book. But for some reason, they were both drawn to it, strangely certain that it held something of importance.

Severus looked up at Harry's silence and sighed, knowing he had to be honest at this stage. The young lion had found the book himself, after all.

"The first three potions, I'm almost certain, are liquid forms of the unforgivables."

Harry had the grace to look shocked at that.

"That's… That's actually possible?"

The professor inclined his head in affirmation. Truth be told, he hadn't thought it was possible. But the lists couldn't possibly be anything else. He had, of course, never attempted such concoctions, but nothing was truly impossible.

He had determined, quite quickly, that the first one held similar effects to the imperious, though he hadn't admitted that finding to Harry immediately. He had simply described the list of ingredients to the boy as quite likely used to brew a mind control potion.

He hadn't mentioned that the next one was probably a torturous nerve stimulant and, after reading the list for the third one, which was a decidedly deadly poison, it all became morbidly clear.

All three required the blood of the caster as one of the base ingredients, which made them undoubtedly dark magic. They also included other questionable and decidedly dark ingredients, such as unicorn blood, werewolf skin and thestral hair. These ingredients were not easily obtained and highly restricted.

"I cannot be certain without brewing and testing them, of course. However, based on the ingredients, I'm reasonably certain that those are the likely effects."

The boy looked ill at the thought. He hastily placed the book on the table and curled into himself on the plush armchair, drawing his knees to his chest in a pathetically defensive pose.

The older wizard silkily broke the silence once again.

"Do you wish to retire for the night?"

Harry nodded, his mind obviously reeling. The silence was unnerving and worrying, even to the ex-death eater.

"Are you quite okay, child?"

The boy nodded again jerkily and stared numbly into his teacup.

Hogwarts' resident golden boy wrapped his cloak tightly around himself as he stared out over the moonlit grounds of the castle. He'd taken to spending the evenings that he wasn't with his potions professor at the astronomy tower in quiet contemplation.

Ron and Hermione barely spoke with him now. They knew his depression was bad and he'd told him he needed space. They respected that, and seemed to be falling head over heels with one another to such an extent that they barely noticed his existence.

That suited Harry. It meant that they no longer asked questions when he disappeared for hours in the evenings. It meant that they no longer noticed whether he was in "detention" or "remedial potions" or just taking time to himself.

Tonight, he was in a particularly dark mood. All he wanted was some heroin to take him away. It would only take one hit and he would be blissfully gone. He ran his hands nervously over his arms, knowing that the need was getting worse, knowing that he was getting dangerously close to slipping back into an addition.

He let his eyes focus on the reflection of the moon on the black lake, trying to distract himself from the tantalizing idea of drugs. He imagined, for a moment, letting the dark water swallow him up. The cold darkness soothing his pain. His mind clouded over with the blackness of his thoughts and he shook his head slightly, bringing up his occlumency shields in an attempt to block out his depression.

This fucking fight with Voldemort couldn't come quickly enough.

Speaking of evil fucking bastards, Harry was abruptly drawn from his reverie by a sharp stab of pain in his forehead that shot outward before dissipating near his temples.

The boy closed his eyes briefly and took a few slow, calming breaths. Despite taking the scar potion religiously, he was noticing the pain returning earlier and earlier each evening the last two or three days. Either the potion was already losing its potency, or else old snake face was finding a way around it.

Either way, it wasn't looking promising for Harry.

He lightly touched the cool vial in the pocket of his robe, smiling to himself at the numbness it would soon bring, before he turned to return to the Gryffindor dorms.

Severus tapped his quill lightly against the parchment, pursing his lips in deep thought.

He read the ingredients a few times, pausing on the darkest ones and noting their order in the list. Surely not… surely it wasn't a potion for that. He'd assumed it was a spell all this time. A potion? How could he have been so foolish.

"Sir? What is it?" Harry's light, curious voice rang out in the silence of the dungeons.

"I think…" the older man trailed off. Surely not.


"I believe this may be…" He trailed off again, trying to find the words.

"I wouldn't have thought it was possible, though."

Harry was running out of patience. He tapped his fingers angrily on the paper in front of him, waiting for the Slytherin to lend voice to his mind.

"We need to brew this. If I'm not mistaken, this is the potion that lends power to the caster of the dark mark."

"It what?" Harry didn't think he understood at all.

"This potion, if my understanding is correct, gives control of the dark mark to the brewer, or the consumer, I'm not certain."

"Speak slowly, sir, I'm not following. Pretend I'm Neville or something."

"The Dark Lord either brewed or took this potion, or a similar one, when he began marking his followers. I never even entertained the idea that the mark is linked to a potion. Harry, I think if you take this, then you will be able to influence anyone who is marked in the same way that the Dark Lord does."

"So… both Voldemort and I could be in control at the same time?"

"I'm loathe to make assumptions without doing more research. However, it appears to be an ordered authority based potion – whoever is the last one to take it, takes the power."

Harry reached over and took the list with trembling fingers. He slowly read each ingredient before promptly throwing up on the floor.

Blood of an enemy, eye of a unicorn, magical essence from the controller, centaur heartstring…

Most of these ingredients were not only almost impossible and illegal to obtain, but also required slaughtering magical creatures. How could anyone create such a potion?