"Shut up, Snape!"
Sirius slammed the Daily Prophet down on the table and sprang to his feet, stepping directly in front of Snape. The werewolf curled up in the corner of the newspaper's front-page photo twitched uneasily, its ears flicking at the sudden disturbance.
"Oh, if it isn't our dear Bigfoot," Snape stepped forward, lowering his voice close to Sirius's ear. "Do you still have that little vial I gave you? I always thought you might find use for it someday."
"Stay away from me," Sirius frowned, stepping back. "If you want to start something, we'll see it through."
"No, no," Snape waved a hand, smoothing imaginary wrinkles on his robes. "I'm Head Boy, you know. Maintaining order is my duty."
"Then get out!" James finally snapped, pointing his wand at Snape.
Snape lightly pushed the wand aside, eyes locked on James's lips to anticipate any sudden attack. "I just overheard your conversation during patrol."
At that moment, Snape spotted Lupin at the far end of the compartment. Lupin clearly saw Snape standing at the door and quickly hurried over, placing himself between James and Snape.
"Calm down, James," Lupin's voice was tired.
Snape's gaze returned to the newspaper.
"Damocles has invented something remarkable. His Merlin Medal is well deserved, isn't it?"
He tapped the photo of the wizard wearing an elegant medal and holding a smoking goblet.
"I imagine it could solve your friend's 'hairy little problem' quite effectively," Snape said pointedly, glancing at Lupin.
"What does that have to do with you?" James ground out, trying to edge past Lupin.
"Oh, what does it have to do with me?" Snape feigned thoughtfulness. "Potter, given your performance in Potions, that 'hairy problem' is only going to get worse."
He turned as if to leave, then suddenly remembered something and glanced back.
"By the way, I'm meeting with the new Head Girl. We'll be discussing this year's work in the designated compartment."
He paused, watching James's face flush red. "Haven't seen Miss Evans for nearly half an hour now..."
A jet of red light suddenly broke through Lupin's block.
Snape reflexively ducked. The curse whizzed past his ear and tore a small hole in the carriage roof.
"Detention, Potter," Snape lazily waved his wand. "Restore!"
The damaged roof instantly healed, looking as good as new.
Turning to the compartment, he said, "Starting tomorrow, for a week—let's see—how about the Forbidden Forest?"
"No," he shook his head. "Filch's office is more suitable for you. I'm sure he'd appreciate a helper. See you later, Potter. You'd better behave; I'll be like a buck following you around, watching for any mischief."
"Get out!" Sirius shoved Snape out of the compartment and slammed the door behind him.
As the door shut, Snape caught sight of James angrily throwing his wand on the floor, while Lupin held him by the shoulders, speaking quietly.
Snape turned and hummed softly to himself, "Potter, that little fool, he can't cast a single curse," as he returned to the Head Boy's compartment.
Pushing open the sliding door, Lily was already inside, holding a copy of the Daily Prophet.
"All went well?" she asked, looking up at Snape.
"Very well," Snape said, pointing to the paper in her hands. "By the way, there's extra news: Mr. Damocles has invented an anti-werewolf potion..."
"Hm?" Lily looked at him.
"Oh, you know," Snape said, "we learned how to identify signs of werewolves back in third year. I've made some mistakes in the past, but now I want to be a better person. As the top two students in Professor Slughorn's class, perhaps we can help someone."
"We can wait for the next issue of Practical Potioneer—they'll have the full recipe," Lily nodded gently. "Until the train arrives, nothing much is left to do, Severus. You can go back to your friends."
"Are you coming, Lily?" The question slipped out before he could stop it.
Lily stared at him a moment, then said, "No, I'm going to find Marlene. Remember to help Hagrid coordinate the first-years when we arrive."
Back at Pandora's compartment, the food trolley had already come through. The table was piled with treats, and their friends were busy trading Chocolate Frog cards.
"Give me one," Snape said, grabbing a card and plopping down next to Pandora.
He tore the wrapper, bit off the frog's head, and glanced at the card. "Here, Aberforth, a Ptolemy card for you—you've been missing this one, right?"
"Wow, Severus," Aberforth took the card excitedly. "What luck! Now I can go claim my prize from Mr. Flume: a year's worth of Honeydukes' new sweets and a free trip to France!"
"You're welcome," Snape mumbled around a mouthful of pumpkin pasty. "It's not like you're short of money."
"Does it make a difference?" Aberforth grinned, slipping the card into his robe. "I'm writing to the Daily Prophet to tell them I completed the set. Some even said Honeydukes never finished printing all the cards..."
The train pushed steadily northward as rain hammered against the windows.
Darkness deepened; the compartment lights flicked on automatically, and the silhouette of Hogwarts loomed ahead.
At last, the train slowed, footsteps and luggage wheels echoed down the corridor.
Snape stood to straighten his robes; as Head Boy, he needed to maintain order during disembarkation.
Opening the door, thunder rumbled overhead. Amid the downpour, he and Lily helped Hagrid calm the first-years.
"First-years, this way..." Hagrid bellowed, but the rain drowned him out.
"Here, Hagrid," Snape said, cloaking himself and stepping beside him, wand raised toward Hagrid's throat. "Louder!"
"First-years—" Hagrid's voice suddenly boomed, startling a few, who nearly fell. He quickly softened it. "Oh, thanks, Severus."
After confirming all first-years were present, Hagrid glanced nervously toward the Black Lake. "Blasted weather. Can you keep an eye on the boats for me?"
"Sure." Snape and Lily exchanged glances, then agreed.
Lily tapped their robes lightly with her wand, whispering, "Waterproof and moistureproof!"
"Great!" Snape called out, leading the first-years toward the nearest boat.
Poor kids were already dazed by the rain; several staggered, mouths agape.
"If we don't drown..." Snape yelled to Lily, "See you at the feast!"
As the boat entered the lake's center, the storm peaked. Lightning struck, illuminating towering waves. Before Snape could warn, a mountain of water surged toward them.
The wind tore at the lake's surface. Behind Snape, four first-years clung tightly to the boat's edge, faces pale with terror.
"Hold on!" he shouted, nearly drowned by the howling wind.
The boat lifted almost vertically, then slammed down hard, drenching them all.
One small wizard screamed as his slight frame was flung to the side.
"Help—" His cry was cut short by a wave that swept him from the boat into the dark water.
"Damn it—" Snape cursed, pointing his wand at his face. "Bubble-Head Charm!"
A transparent bubble instantly enclosed his head. He took a deep breath and plunged into the churning lake.
The cold water swallowed him whole. Snape flicked his wand. "Lumos!"
The wand tip glowed faintly, casting light a few feet ahead in the murk.
He dove hard, ears filled with his rapid breathing and the lake's gurgling currents.
Suddenly, a blurry figure passed at the edge of his vision.
Snape whipped around, wand aimed ahead.
In the dim light, silver-green scales shimmered in the darkness.
Mermaids—and not just one, but at least five or six—armed with spears, their strong silver tails slapping the water as they swam swiftly toward him.
Their skin was iron gray, their dark green hair wild; their eyes yellow, teeth jagged and yellowed; necklaces of rough stones strung on thick cords hung from their necks.
"Stay back!" Snape tried to shout, but his voice came out muffled through the bubble.
He gripped his wand, ready to cast—but the lead mermaid, a male with a long green beard and a shark-tooth necklace, suddenly changed course and dove downward.
Following his gaze, Snape saw a small figure sinking slowly.
The boy no longer struggled; limbs relaxed and spread, bubbles spilling from his mouth.
The mermaids quickly surrounded the sinking boy, their powerful arms cradling him, pushing him toward Snape.
Snape caught the boy—his face pale, lips blue—and immediately cast a Bubble-Head Charm, then a Reviving Charm.
The boy coughed violently inside the bubble, spewing water, then began shallow breathing.
Snape turned to the mermaids, pressed his wand to his chest, and made a gesture learned from the full version of Fantastic Beasts and Where to Find Them: a circle over the heart, then an outward sweep—a mermaid's way of saying "thank you."
The leader tilted his head, baring sharp teeth, then led his companions into the dark depths.
Snape held the boy with one arm and swam vigorously toward the surface.
Splash! Breaking the lake's surface, a flash of lightning lit the whole expanse.
Snape gasped for air, looking around to see the nearest boat just yards away.
Lily stood at the bow, wand raised, its tip casting light over the water.
"Severus! Here!" she called.
Snape swam desperately toward the boat.
Other students scrambled to haul them aboard.
"Is he all right?" Lily asked anxiously, checking the boy over.
"He swallowed some water," Snape panted, breaking the bubble, "and the mermaids... they helped a lot."
The flotilla pressed onward. At last, the silhouette of Hogwarts castle appeared.
As they stumbled ashore, Hagrid emerged from the rain, massive and dripping, his beetle-black eyes full of worry.
"Thank Merlin, you're safe!" he said, thumping Snape's back with enough force to knock him into the mud. "How's the little one?"
The boy had awakened, still trembling but looking much better.
"All right, children, get inside and warm up!" Hagrid helped the remaining students off the boats. "The Sorting Ceremony will begin shortly."
Their footsteps splashed loudly as they hurried up the stone steps.
"Oh, I can't imagine crossing the lake in this weather," Snape muttered, magically drying the students' robes. "Old traditions and strange stubbornness."
"Ah!" A giant red water balloon fell from the ceiling, bursting over the first-years.
The drenched children staggered and fell, screams ringing out as they pushed each other.
Looking up, Snape saw the prank-loving poltergeist floating over them more than ten feet above—a bell-topped hat perched on his head, an orange bow tie, and a water balloon in hand.
"Peeves!" Snape shouted angrily, drawing his wand. "Come down here!"
The poltergeist chuckled, raising another