It was early morning of the day Carlos dreaded each month, the enchanted ceiling showed heavy clouds, mirroring his worsening state. He was pale, hands trembling slightly as he tried to eat. His usual sharp wit and sarcasm were dulled, an exhausted look etched upon his face. Oscar noticed Carlos from across the hall where he sat with Logan. He had caught the way Carlos was gripping his fork unnaturally tight, the dark shadows under his eyes, and how he flinched at every sudden noise. He didn't move to comfort him, only watching carefully from a distance.

Lando had seen him unwell many times, but this worried him.
"You don't look well, no offence Carlos. You've barely touched your food, and- Merlin, are you shaking?" Charles gasped, brow furrowed in deep concern for his friend.

In potions class, Carlos had been struggling to focus, Oscar took note of how his hands shook while handing ingredients or performing spells, he had messed up a step, which Oscar couldn't remember him ever doing. "Okay, enough. You're barely holding yourself together. What's wrong with you? You look like... you look like you did in that corridor... Carlos?" Oscar spoke in a hushed tone to avoid attention.

"What corridor?" He denied weakly, knowing it was pointless trying to maintain that lie. "I'm all good, vete a la mierda."

Oscar snorted, "Yeah, I recognised that one, mate. You're lying, I can see it all over your face. You're scared of something- and whatever it is, it's happening tonight, isn't it?"

Carlos paused, face scrunched up in poorly disguised pain. "You don't know what you're talking about." Oscar was convinced that something serious- something dangerous, was going on, and Carlos somehow was heavily involved in it.

"Whatever, you're seconds away from blowing up the cauldron shaking like that, let me at least help with that."

Carlos tiredly looked up, "I don't need help."

"Yeah? Because from where I'm standing it looks like you do."

Lando watched them from where he was partnered with George, his jaw clenched. The fuck? They don't even like each other.

Between classes, Lando intercepts Carlos and Oscar, his frustration boiling over. "Why are you following him around all day? Since when do you care about him?"

Oscar shrugged, "Since he started looking like he's about to collapse any second. Someone's gotta keep an eye out and you're clearly not prepared to."

"That's not-"

"¡Cierra la puta boca!" Carlos yelled, voice cracking under the strain, storming off to his next lesson by himself, leaving Oscar standing with Lando, tension thick enough to cut. "Well done," Oscar said, glaring at him as he snapped back.

"Oh, so this is my fault now? You're the one who's been hovering around him like some- some overprotective shadow all day!"

"Because someone has to, Lando. Have you even looked at him? Let alone speak to him. He looks as though he's about to drop dead. Whatever's wrong with him he refuses to say," Oscar calmly replied, unfazed by Lando's annoyance.

"You think I don't know that? You think I haven't noticed? He's my best friend, Oscar. I know him better than anyone."

"Then why aren't you doing anything about it?"

They stared at each other briefly until Lando looked away. "I've tried, but he won't let me in. He won't let you in either, by the way, so don't act like you're some kind of hero."

Oscar softens slightly, glancing in the direction Carlos left. "I'm not trying to be a hero, I'm just- look, something is wrong, and it's not just stress, or lack of sleep or whatever shit he's claiming. You can feel it too surely."

"...Yeah."

"Look, I don't care if you suddenly hate me, you can glare at me all you want, call me names, whatever. But we're on the same side here, whether you like it or not. Besides, you're the one always encouraging me to be nicer to Sainz."

"Yeah, well, doesn't mean I have to like it," Lando grudgingly said.

"Didn't expect you to."

The sun was rapidly lowering, the sky slowly becoming littered with stars. Carlos had claimed he "needed some air" and had left the school, yet Oscar was still suspicious and deeply unsettled by Carlos' earlier behaviour. He followed him out the castle and saw him visibly struggling- sweating, stumbling, clutching at his chest as the moonrise approached.

"Carlos, where are you going?" He shouted after him.

Carlos didn't even turn around, "Go back, Piastri. Please. Just this once... listen to me," voice hoarse.

"Not happening, I'm not gonna just let you go wandering off in the night-"

"I said go!" Carlos stumbled and Oscar instinctively grabbed him to steady him. He tried to keep him upright, but Carlos was feverish and in pain. "I have to get to the Willow...leads to the- the Shack... please... it's not safe here."

Oscar didn't understand but picked up on the urgency and fear in his voice. "What's at the Shack, Carlos? What are you running from?"

Carlos' panicked voice interrupted him, "Not now. Please, Oscar. Just help me get there, I can't-"

"Alright. Come on, lean on me, we'll get there."

Oscar more dragged Carlos as he grew weaker still. They stop suddenly, Oscar now scared. "Carlos, you're scaring me. What's happening to you? Are you cursed? Poisoned? Tell me something!"

"Please just keep moving." Oscar noticed the full moon starting to rise above the horizon. He doesn't connect the dots yet but feels his dread intensify.

They finally reach the Whomping Willow, Carlos grabbing a stick to press the knot to freeze it. Oscar realised that Carlos knew this place well, far too well.

"How do you know about this place? No one comes here- this isn't normal, Carlos!"

"Because it's the only place safe enough... safe from me," Carlos struggled to reply. They stumble together through the tunnel, Carlos clutching his chest, breathing erratic. Oscar stops him one final time, grabbing his arm.

"Carlos, please, whatever this is- tell me, I'm not leaving you like this."

"You can't help me, Oscar. You need to go."

"I'm not leaving you alone in some bloody haunted shack-"

Carlos desperately pushed him away, "If you care about me at all, you'll go. Now!" He stumbled into the darkness of the Shack, the sound of the door slamming echoes back at Oscar. He hesitated at the entrance, fear and confusion warring inside him.

He sat just outside the entrance, hearing sounds- unearthly growls; furniture splinting; a haunting, inhuman howl.

He felt his face drain of colour as he slowly began to piece together what he just did. He didn't have visual confirmation, but he knew: Carlos isn't just sick, he's something else. "This isn't possible. This can't- no. But the moon... the Shack... the sounds..." He remained frozen in place for a while before running back towards the castle, fear and guilt gnawing at him.