McGonagall's eyes went slightly glassy for a moment before she seemed to catch herself, clearing her throat sharply and turning back to the board with military precision.
"As I was saying," she continued, her voice slightly rougher than before, "the persistence of biological transformation depends on several factors."
Hermione couldn't look away from the front of the classroom. She watched McGonagall teach with new understanding—the way she gripped the edge of the desk, the careful positioning of her body, the slight flush on her cheeks when Seamus slouched in his chair in a way that emphasised his shoulders.
She's attracted to him, Hermione realised with dawning horror. The... the thing... it reacts to attraction. It gets—
She became suddenly, acutely aware of Harry sitting two seats away.
Harry, who had taken off his outer robe because the classroom was warm.
Harry, whose white shirt was slightly untucked.
Harry, who chose that exact moment to run a hand through his perpetually messy hair and flex slightly.
Hermione's cock twitched.
No, she told it firmly. Absolutely not. Down.
It did not go down.
It did the opposite of down.
"Oh no," she whispered.
"You okay?" Ron muttered from beside her.
"Fine! Completely fine! Just—just remembered something I forgot to do."
She grabbed her textbook and held it in her lap, pressing down firmly. The pressure made things worse and better simultaneously, which was not a combination she'd ever expected to experience.
At the back of the room, she heard Luna say, quite clearly, "Gerald is very excited today."
Parvati Patil turned to stare at her. "What?"
"Nothing. Just talking to myself."
McGonagall's chalk snapped.
"I think," the Professor said tightly, "we'll end class early today. Read chapters fourteen through sixteen. Essay on the ethics of human transfiguration due Thursday. Dismissed."
The students began gathering their things, confused murmurs rippling through the room. McGonagall never ended class early. Never.
Hermione was the first one out the door.
She made it approximately seventeen steps down the corridor before Lavender caught up with her.
"Did you see?" Lavender hissed, grabbing her arm. "Did you see McGonagall? She was—and Seamus was—and it—"
"I saw," Hermione said grimly.
"It reacts to things. Hermione, it reacts to arousal."
"Yes, I noticed."
"How am I supposed to live like this? Won-Won is coming to visit next weekend! What am I going to do when I see him?"
Hermione didn't have an answer.
They were joined moments later by Luna, who drifted out of the classroom with serene unconcern. "That was a very educational lesson," she said. "Though I don't think she meant to teach us what she taught us."
"Luna, please," Hermione groaned.
"Gerald learned a lot. He's very intellectually curious."
"Please stop naming it."
The three of them retreated to Moaning Myrtle's bathroom—the only place in the castle guaranteed to be free of unexpected visitors. Myrtle herself was sulking in the U-bend, muttering about "living people and their living problems," which suited them fine.
They were not alone for long.
The door banged open, and Pansy Parkinson stormed in, her face thunderous.
"This is YOUR fault, Granger," she snarled.
Hermione's heart stopped. "I—what—how—"
"You're the only one obsessive enough to brew something this catastrophic. I don't know how you did it, but I know it was you."
"You don't know anything—"
"Four Gryffindors and one Slytherin?" Pansy advanced on her. "The odds of that being random are astronomical. Someone targeted specific people, or someone fucked up in a way that affected people near them. And you, Granger, are always the one fucking things up with your 'extra projects' and your 'additional research.'"
Hermione's silence was damning.
"I knew it." Pansy's eyes blazed. "I knew it. What did you do?"
"It was an accident," Hermione whispered. "I was brewing an Essence of Empowerment—it was supposed to enhance magical stamina—but I misread an ingredient, and the potion failed, and I gave it to a house-elf to dispose of, and—"
"And she put it in the pumpkin juice," Lavender finished, comprehension dawning. "That's why it tasted different. That's why—oh my God, Hermione!"
"I DIDN'T KNOW SHE WOULD DO THAT!"
"You gave a failed potion to a house-elf! What did you THINK would happen?"
"I thought she would pour it out! Like I told her to! I didn't think—"
"No, you didn't think! You never think about consequences, you just barrel ahead with your books and your brilliance, and now I have a PENIS!"
"We all have penises!" Hermione shouted back. "You think I wanted this? You think I'm enjoying this?"
"Um," Luna said thoughtfully.
Everyone turned to stare at her.
"Never mind," she said. "Continue arguing."
"What do you mean, 'um'?" Pansy demanded.
"I mean nothing. Gerald and I have no comment."
Before anyone could respond, the door opened again.