"You haven't come to see me for one hundred and fifty-three days."
When Snape ignored the Out of Order sign and pushed open the door to the second-floor girls' lavatory, Moaning Myrtle suddenly drifted out from behind a faucet.
A mist clung to her pearly spectacles as she hovered in the doorway, her voice full of wounded reproach. "You said you'd come visit me... I've been waiting here all this time..."
"Myrtle!" Snape jumped, startled by her sudden appearance, and took half a step back. "Well, I'm here now, aren't I?"
As he spoke, he quickly slipped into the lavatory and pulled the door shut behind him, not wanting any passing students to see him entering the girls' bathroom.
When he passed through Myrtle's spectral form, he was instantly seized by the sensation of plunging into a bucket of ice water. He shuddered involuntarily, his teeth clattering softly together.
"Not only that," Snape said, bringing his hands to his mouth and blowing warm air onto them, "would you like to live somewhere else? A place better than this? I even have a new friend I'd like to introduce you to."
"A new place?" Myrtle's eyes flickered with a hint of hope, but the light quickly faded, leaving her looking dejected. "I don't want to be laughed at again, or driven away."
"This place is very well hidden, trust me," Snape said gently. "Would you like to come and have a look? If you don't like it, you can always come back."
Myrtle hesitated, then gave a small nod. "Alright. I'll go take a look."
Snape told her where they were headed, but to his surprise, Myrtle simply floated upward, right through the ceiling.
"I'll wait for you up there, Sev."
Snape broke into a jog, darting through winding corridors toward the painting of the gigantic troll dancing ballet on the eighth floor.
By the time he arrived, Myrtle was already there, hovering in midair with a faint, expectant bounce.
"No one saw you, right?" Snape asked.
"No," Myrtle replied. "There's no one around here."
"Good," Snape said, catching his breath. Pointing at the seemingly ordinary stone wall before them, he added, "Myrtle, could I trouble you to go inside this white wall and see what's in there?"
Myrtle gave him a puzzled look but didn't ask questions. She obediently drifted into the stretch of wall that hid the entrance to the Room of Requirement.
A few seconds later, she popped back out, her face full of confusion. "There's nothing in there, just stone."
"Thank you, Myrtle," Snape said with satisfaction, nodding. "That means not only people, but even ghosts can't enter directly."
"What place is this?" Myrtle asked, looking even more confused. "What's inside?"
"Just wait a moment, you'll see soon enough."
After saying that, Snape approached the wall and rapped on it three times with his knuckles. Then, at a slower rhythm, he clapped his hands together three times, and finally tapped the wall three more times quickly.
With a low creak, an old oak door materialized on the wall.
The door opened with a squeak, and Pandora peeked out from inside. "Come in, quickly."
Snape slipped inside at once, then leaned back through the doorway to beckon Myrtle. "Come on in!"
Once Myrtle floated in, he promptly shut the door behind them.
"Step one confirmed," Snape said cheerfully to Pandora. "If someone's inside the Room of Requirement, even ghosts can't get in."
"Oh, right," he turned to Myrtle. "Do you know Pandora?"
"Yes," Myrtle said softly, circling Pandora once. "A girl who, like me, gets laughed at..."
"For us, this place is perfect, isn't it?" Myrtle said excitedly. "Even Peeves won't be able to come in here!"
"I don't think he can, Myrtle," Snape replied. "But we'll need your help to test a few more things."
Myrtle flipped upside down happily, her eyes glimmering with anticipation. "Does that mean I get to live here now?"
"I think so," Snape said, glancing at Pandora. Pandora smiled and nodded at Myrtle in agreement.
"Is there anything I can do to help you?" Myrtle said primly, bowing politely before breaking into a delighted giggle.
"The rule of this place," Snape explained, "is that as long as someone's inside, no one outside can open the door.
"What we still need to know is whether the same applies if it's a ghost inside."
"In that case," Myrtle said, adjusting her glasses, which flashed with pearly light, "the next step is for you two to leave me in here."
"Clever," Snape said approvingly. "But first, you should see whether you can pass through the walls inside this room."
Myrtle immediately tried, diving into the wall of the Room of Requirement.
A moment later she reappeared, shaking her head. "No. Same as outside, it's all endless walls."
"Excellent," Snape said, attaching a hook to the doorknob. At the other end of the hook was a peculiar-looking device. "This contraption will pull the door open when it hears a loud sound."
"Remember the rhythm I used earlier, knocking and clapping?" he asked Myrtle. "Three short, three long, then three short again. Only open the door when you hear that pattern, alright?"
He demonstrated the rhythm twice more, then pressed his ear to the door, listening for sounds in the corridor before giving Myrtle a nod.
Myrtle took a deep breath and let out a piercing, ear-splitting scream.
"Stop!" Snape quickly raised his hand to halt her, as the door had already been tugged open a crack by the magical device Pandora had crafted, its core made from the vocal cords of an Erkling. "You don't need to scream once it's open!"
Then he and Pandora stepped out of the Room of Requirement and watched as the entrance vanished once more into solid wall.
After testing that the door couldn't be opened by ordinary means, Pandora cast Muffliato down both sides of the corridor, then recreated the same sound pattern.
The door opened again. They entered once more.
"Brilliant!" Snape and Pandora exchanged a triumphant high five, both grinning from ear to ear. "This place is going to be much safer for us now! Myrtle, if you ever want to go out for a walk, just let us know in advance."
"Go out? No," Myrtle said. "I like this place, with sunlight, even! As long as you two come visit often."
Then she giggled mischievously. "What an odd little bunch we are, Moaning Myrtle, weird Pandora, and Sev who likes watching naked bottoms..."
"Hey!" Snape blurted out, unable to stop himself. "Weren't you supposed to stay in your bathroom?"
"Sometimes I sneak out," Myrtle said with a sly grin. "I've seen yours too..."