The Patronus. More than a defensive charm, it was a testament to a wizard's inner state, an unspoken proof that their mind remained sound, and their soul still clung to light and goodness.

Anyone twisted by dark magic, or soaked too long in it, those with only malice left in their hearts, such witches or wizards could never cast a Patronus. Their souls had long since lost any refuge untouched by shadow.

That was precisely why Vaughn had brought it up first.

Not just because it was notoriously difficult to master, but because it served as a perfect marker.

At the very least, it would reassure Dumbledore.

When Vaughn left the Headmaster's office, he carried a heavy tome under one arm: The Origins and Evolution of Memory Magic. A rather poetic title for what was clearly a Ravenclaw's work.

He suspected the author was likely an over-enthusiastic academic with too much time and a dramatic streak.

Back in the Slytherin common room, Vaughn practically dove into the book the moment he sat down.

The text laid out the entire field of memory magic in detail, from its ancient origins, to modern applications and spells. It covered familiar territory, like the Forgetfulness Charm and Occlumency, and spells Vaughn longed to learn, like Legilimency. But there were others too: False Memory Hexes, Dream Charms, and even Nightmare Inducers.

The book explored spells from other branches of magic that required memory as a fundamental component. Alchemy alone included tools like Pensieves, memory orbs, enchanted portraits, and auto-writing quills. Though the crafting methods weren't detailed, their reliance on memory was thoroughly explained.

"Advanced Transfiguration requires memory? Turning an object into a living thing... The process mimics the injection of memories, false ones, of course, but vivid enough to pass for a soul…"

That section made Vaughn pause.

He flipped back to the title page. There, in elegant script, the author had written:

"Memory is the cloak of the soul."

When he'd first read it, he thought it was just more Ravenclaw nonsense.

But now… soul, indeed.

His interest in the book only deepened. So much so that he even brought it with him the next day to Professor Snape's office, where he spent time studying potion ingredients.

When Snape saw the book, he froze.

"Where did you get that?" he asked sharply. "You already had it? Then why did you ask me for a copy last time?"

"Oh?" Vaughn raised a brow, feigning innocence. "The book on memory magic you promised to give me during the summer - is this the one? Dumbledore gave it to me."

Snape's expression soured instantly. It wasn't hard to imagine what he was thinking: something along the lines of cursing Dumbledore for saying one thing and doing another behind his back.

Vaughn had suspected all along that Snape's "summer delivery" plan was really just a delay tactic. The man probably wanted time to convince Dumbledore not to hand over something this powerful.

But Vaughn didn't care how uncomfortable he made him. Smiling, he said, "Professor, I suppose we'll need to renegotiate our deal then?"

Snape's jaw twitched. "The Quidditch season is starting soon. Beat Potter, and we'll talk."

Vaughn squinted at him. "You're not planning to weasel out of our agreement, are you?"

Snape didn't answer.

After ten seconds of being stared down by a cheeky Slytherin, Snape stormed off in a swish of robes, clearly fuming.

Renegotiate? If he gave in any further, the next step would be teaching Vaughn actual Dark Arts.

Not a commitment one made lightly.

Vaughn, unfazed, stayed behind to continue studying in the dungeon. When he got tired, he flipped through more of the book. Unfortunately, most memory spells required a target to practice on.

Luckily, a perfect candidate showed up on his own.

And even better, he was grateful for the opportunity.

That night, Harry met Vaughn in the Room of Requirement. He had received a note and snuck out quietly.

The moment he saw Vaughn, he blurted out, "Thank you! Really. For doing this so late. If it weren't for you, I don't know what I'd…"

He looked awful. In just a day, the bags under Harry's eyes had darkened to the point they could rival the ones he'd sported last month after Oliver Wood's infamous Quidditch drills.

Clearly, something had shaken him badly.

"Don't mention it, Harry. We're friends. Friends help each other out, don't they?"

Vaughn offered the platitude smoothly, then leaned forward with a little sparkle in his eyes. "So… shall we begin?"

"Already?" Harry blinked, caught off guard.

Still, he obeyed and sat down opposite Vaughn.

Tonight, the Room had been shaped into a luxurious lounge at Vaughn's request. Leather armchairs, thick wool rugs, it was all terribly soft and comfortable.

After all, memory magic didn't damage the surroundings, and a relaxed state of mind would help Harry stay calm.

Also, Vaughn thought, it made his experimental practice much easier.

He would never admit he had chosen this plush setup for his convenience.

Vaughn sat upright across from Harry, book in one hand, flipping through pages as he spoke.

"Before we start, I should warn you. Learning Occlumency is a long and difficult process. To speed things up and help you recover from the lingering effects of that dark curse, I'll need to perform Legilimency on you the entire time. You know what that is, right?"

Harry looked puzzled. "Only from this morning, when you mentioned it for the first time."

"Perfect," Vaughn said, nodding solemnly.

"…Wait, what?"

"Ahem. I mean, that's a very good answer," Vaughn said smoothly. "To put it simply, Legilimency means I'll be diving into your mind, poking around your memories, shaping and playing with them. Your job is to experience it. Don't resist. Don't panic. Be as cooperative as possible. Understood?"

Harry's face went pale. "That's the simple version?"

Words like poke, manipulate, and play with weren't exactly soothing.

He had a sudden urge to ask if he could back out.

But no, that wasn't an option. Even though he hadn't felt any worse all day, just hearing the words dark magic was enough to steel his nerves.

So Harry straightened his back and said, "Alright. Let's do it, Vaughn."

What a perfect target.

Vaughn gave a silent cheer, raised his wand, and began casting.

As expected, the first attempt failed. Neither of them was surprised. After two more failed tries, Harry even started to look relieved.

Maybe he wouldn't have to be poked and played with after all.

Unfortunately, just as that hope bloomed in his heart--

Legilimens!

The spell struck true.

Vaughn had finally found the rhythm. Enough magical power, the right incantation, and most critically, the right emotion. He had to want it. Really want to dig into someone's secrets.

And he had wanted Harry's.

The moment it connected, Vaughn felt it.

His awareness twisted, his magic pulled along into a thick, dreamlike world.

Fog churned in every direction, and through the mist, images flickered.

Memories.

All from Harry's point of view.

There was Vaughn, raising his wand. Harry walking through the halls. The Gryffindor common room. Ron and Hermione at his side.

Every memory was exposed.

Even the dreams.

One hazy scene shimmered into view. It was sweet. Innocent. Just a moment in a dream, where Harry gently took a girl's hand…

"NO!"

The scream came from somewhere far away, but it yanked Vaughn straight out of the memory space.

He blinked.

Harry's face was crimson, redder than a sunburnt tomato.