Truly, nothing says Gryffindor-Slytherin bonding like mutual loathing and shared hypothermia.

...

Sirius' POV:

»And why are we splitting up?« Lestrange's voice cut through the stillness, her hands flailing about in confusion. Her eyes were wide, betraying a hint of panic.
»Does it scare you?« I taunted, my tone deliberately provocative.
The Slytherin stiffened, realising she had shown a sliver of fear in front of a Gryffindor. Her light curls bounced as she shook her head defiantly, arms crossing over her chest. »Me, scared? Pft!« She quickened her pace, drawing level with me, her eyes flicking back towards the shadows behind us. »As if! A Slytherin shows no weakness. We don't even possess any!«
»And what was that just now?«
»What do you mean?«
»That tremble in your voice, maybe?«
»I don't know what you're talking about.«
»Aha, so I must have imagined it, then.« I raised an eyebrow, my grin widening. To see Lestrange squirm was oddly satisfying. For once, she was not as insufferable.
We had already put some distance between ourselves and the others. I hoped they were doing alright, though that thought was secondary. Lestrange must not discover the scene the other Marauders would soon stumble upon. So, dealing with her fell to me.

But is this really the lesser evil?

Lestrange stumbled through the snow, voice rising as she insisted, »Of course, you're imagining it.«
»At least my imagination works,« I countered. »I can think of beautiful things, unlike you.«
»Ha, that-« she began, but a sudden howl cut her off. This one sounded more desperate than the first. An involuntary shiver ran down my spine. Lestrange flinched too, though she managed to regain her composure quickly. It was not every day one heard the cry of a werewolf, especially when the moon was neither full nor even visible in the sky.
Even for me, it was unsettling, confirming Prongs' suspicions about Ethan J. Aquila were more than idle speculation. The key was ensuring Lestrange did not connect this to Phil. Everyone knew her father was a werewolf, a fact whispered throughout the wizarding world.

How awful that must be, I thought.

Conflicted, I found myself torn between wanting to be with the other Marauders and knowing it was crucial to keep Lestrange in the dark. The primary goal was simple: prevent her from discovering that Phil was a werewolf. If she did, it could lead her to Remus, and that was a risk I could not take. The signs were all too obvious: the same exhaustion after a harrowing night, the dark circles under their eyes before a full moon, the scars marking their bodies, and that ever-present fear of rejection.
»The wolves are getting more aggressive,« I said, attempting to steer the conversation.
Lestrange shot me a sceptical look. »Wolves?« Her disbelief was palpable. »Black, you're not seriously suggesting those are ordinary wolves, are you? Please, I’m not an idiot. You might be, but I’m not.«
»What else could they be? Werewolves prowling the Forbidden Forest in broad daylight? Now who's being foolish, Lestrange?« I laughed, keeping my tone light. »You overheard us talking about Phil and wolves, didn’t you? Here they are. Care to get closer to the howling?«
»No…« she said slowly, both of us coming to a halt. The wind swirled around us, carrying the echo of the howl. Lestrange looked back in the direction it had come from.
»Why would anyone run into the forest?« she muttered, her thoughts evidently straying to Phil. As a Lestrange, she would have heard the tales about Ethan J. Aquila, though in our circles, those stories were dismissed as mere fantasy. The idea that Aquila had managed to breed werewolves capable of retaining human consciousness was considered a myth. He had vanished from the wizarding world years ago, and his name was now synonymous with rumour. I prayed it would stay that way for Lestrange.

The thought is maddening. A werewolf that can transform like an Animagus...

»I can't answer that,« I replied carefully. Lestrange's gaze shifted to me. »Phil hasn’t been here long and hasn't shared much. I only know from Remus that she likes herbs and animals, lived on a secluded property until her mother passed. Her mother homeschooled her, but now Phil is here at Hogwarts. Given her family name, she probably has her reasons, ones we might even understand. Perhaps the forest feels like home to her.«
I wove my story carefully, keeping it close enough to the truth that it might hold water. I would have to remember my own lie, in case I needed to share it with the Marauders or Phil herself.
Fortunately, my words seemed to placate Lestrange. When I mentioned our families, she turned her gaze back to the distance. No one could deny that the Black and Lestrange families were infamous for the way they raised their children. We did not know Phil's full story, but the possibility of shared trauma was enough to make Lestrange pause.
»Let's find this strange Phil, then,« Lestrange said, brushing past me. »I don't care about the creatures in this forest, or why you and your weird friends know so much about them. You lot are always sneaking around the castle; it's no surprise you'd stick your noses into the dirt out here too.«
I bit back a retort, satisfied that she was moving in the direction I wanted. Together, we trudged through the grey forest, the snow rendering the world a stark white.

My steps stomped through the snow. I intended to take a wide detour with the Slytherin, then emerge at the castle. Of course, it was a great pleasure for me to walk through the forest with her in winter and in a snowstorm. Obviously, it was meant sarcastically because, to be honest, Elizabeth Lestrange was not the joy personified.
»Watch out, Lestrange!« I called suddenly, grabbing her shoulders to steady her as she nearly fell.
»Damn it!« she hissed, glaring down at her right foot, buried in snow up to her calf. I let out a malicious chuckle.
»Don't laugh like that, Cur!«
»Why always 'Cur'?« I asked, genuinely curious. My grip on her shoulders tightened as I looked into her green eyes, trying to understand. Lestrange could not know about my Animagus form, yet the nickname was fitting.

Unfortunately...

»Your long hair reminds me of a matted stray dog.«
»Seriously?«
»What?« she asked, feigning innocence as her eyes met mine. »If you don't want to hear the truth, you should keep those questions to yourself. It's not my fault if you're sensitive.«
After that charming display of kindness, she finally managed to pull her foot free from the snow, leaving her boot stuck behind. A small whimper escaped her, and she found herself leaning against me for balance, her hand resting on my shoulder like it was a toxic surface. Her disgust was so obvious, I could not help but laugh.
»See, if you weren’t always sticking your nose into other people’s business, you’d probably be in the Great Hall right now, enjoying lunch and a warm cup of tea,« I said.
Lestrange shot me a glare. »You can let go of me now.«
»Ah, I thought you were enjoying my company, considering we’re such good friends,« I replied with a mischievous wink.
She shoved my hands away, but since she was balancing on one leg, she wobbled, forcing me to catch her by the waist. This sudden proximity between us felt different, and for a moment, I was aware of how close we were, of how I had never been this close to a girl before. But I had to remind myself - Lestrange was not just any girl. She was a detestable snake, a symbol of everything I loathed.
Our faces were inches apart. I could see the discomfort etched in every line of her face.
»Is my touch that repulsive to you?« I taunted. »So unbearable that a 'Blood Traitor' like Black saved you from falling into the cold snow? Twice?«
Snowflakes clung to her hair, her black eyelashes dusted white.
»Not only does your appearance remind me of a dog, but so does your smell, Black! It’s almost nauseating!« she snapped, jerking away from my grip. She slipped her boot back on and muttered, »Let’s keep going.«

As per Princess Lestrange’s wishes, we continued our trek in silence, weaving through the grounds with the castle's silhouette growing closer. The snowstorm had abated, but the cold had seeped into my bones, making each step more taxing than the last. The whole outing had been a mistake, and the cold, complaining company did not help. I hoped the other Marauders had managed to find Phil by now.
Lestrange, still muttering complaints about the cold, trudged beside me as we finally reached the castle entrance. A familiar figure stood waiting there. Prongs was tapping his foot impatiently, his Gryffindor scarf flapping in the wind. His glasses were fogged, evidence that he had not been waiting long. As we approached, he cleared his throat.
»Don’t worry, we found her,« he said, his voice filled with relief. Lestrange nodded curtly and brushed past him, making her way into the castle.
»Did our dear Lestrange find the adventure too overwhelming?« I called after her.
She turned, her lips tinged with blue from the cold. I felt no pity for her, though.

Yes, the others found Phil faster with her help, but since Lestrange had been so stubborn about not telling us the location, she had to freeze.

»Your mere existence reminds me of what true hatred feels like, Black,« she retorted before disappearing down a corridor. I chuckled dryly, but the sound died as quickly as it had come. I remembered why I had been out in the cold with the Slytherin in the first place.
»What happened, Prongs?« I asked, as we started walking. My fingers raked through hair damp from the snow.
»Exactly what it sounded like,« he said, leading the way towards the Hospital Wing. »Phil can transform into a werewolf at will, and she retains her consciousness. It’s a mess. She was in such a state when we found her. Moony took a good fifteen minutes to calm her down. She’d been chased by wolves. They were trying to rip her apart. Horrible, really.«
»Our Moony managed to calm someone down?« I asked, genuinely surprised. Remus was usually the one who needed calming. His version of comfort mostly involved offering chocolate or muttering logical reassurances. It was odd to think of him consoling someone else.
»Is she in the Hospital Wing?« I asked, shifting the conversation back.
»Yes, Moony and Wormtail are with her. Dumbledore’s probably there by now too.«
We continued down the corridor, the silence between us heavy with the events of the morning. I still was not sure what to make of it all.