A Circle of Flame- Sirius Black x OC

Chapter 39

"Now, pause for a moment during your second observation." Slughorn beamed as he looked over the chamber. A bright yellow cap was perched over his brows as he fumbled with the pocketwatch on his left side. "What do you see? Has the texture changed? The colour deepened? No note is inconsequential."

Pursing her lips, Liza sat back as she let her wrist relax from stirring the cauldron. Slughorn had allowed them to brew a potion of their choice for this unit's lesson. The polyjuice was not exceptionally advanced, but certainly time consuming. Liza had only selected it knowing that she could swipe some of the brew before turning in a sample. It was a rather useful tool.

A sickly smell rose from the cauldron to her right and Liza gagged, nearly tasting the moldy aroma on her tongue.

"Merlin, Snape. Are you boiling a blast-ended skrewt?"

Her potions partner scowled ungratefully, his hair damp from the green steam that enveloped his features. A vial of powdered silver was upturned near his elbow, particles gleaming in the half-light as they scattered over the table.

Liza frowned. Silver was rarely used in potions. It had a fickle nature and could turn on its brewer in an instant, causing explosions or poisonous gas. Slughorn didn't even permit it in the class stores.

"Where—"

Before she could finish, Snape had already tucked the vial underneath his sleeve and vanished the remnants with the flick of his wand.

"Mind your own business," the Slytherin sneered, not even casting a glance in her direction. "I can summon Black over if you'd prefer."

Pulling a grimace, Liza tried not to turn her head towards where Sirius and James were working on Felix Felicis (albeit rather unsuccessfully). They had requested to take an extra period with the Slytherins just to complete it. However, she had paid Sirius far too much attention that day. If she wasn't careful, someone in her house would catch notice.

"We both know he would ruin our marks."

Snape grumbled under his breath as he began to slice a leafy stem into even strips, peeling its petals away from the rest of the limb. The angle of his knife was even and deadly precise. Liza tried not to imagine being at the opposite end of his wrath.

She frowned at the purple shade. "Is that monkshood—"

"Wolfsbane," Severus snapped, not looking up as he separated each segment of the stem carefully.

"Same thing—"

The Slytherin slammed down his knife and shot her a dark look. His obsidian eyes sparked with a pulsing annoyance. "Not in this case."

Utterly bewildered, Liza watched in silence as Severus rubbed the petals between his fingertips, encouraging the juice of the flower to escape its bonds.

"It would go faster if you used a pestle." Liza continued despite the increasing tension of Severus's shoulders. "It won't compromise the structure if you stiffen it with a bit of flax seed."

There was a slight pause as Severus opened his mouth to argue.

Then he clenched his teeth and summoned the mortar and pestle before grinding each flower carefully. Liza observed his movements with approval. The Slytherin may have been a git, but he was sure to be a Potion's Master.

"Only you would use wolfs—" Liza's comment caught in her throat as Severus's eyes flickered over towards Remus and Peter. Based on the ash dusting the latter's shoulders, their brew was not going as successfully.

But there was a hint of guilt in Severus's gaze that startled her. It was utterly foreign.

"Are you—" Liza looked back down at the ingredients that littered his workspace, each carefully piled on their own section of the cutting board. "Are you trying for a cure?"