The topic is Myrtle

As soon as Anthony stepped into the corridor on the second floor, he immediately heard Myrtle sobbing and wailing in the bathroom again. Professor Quirrell's door was closed, and to avoid Myrtle's cries of resentment, the garlic in the portrait had fallen to the corners of the frame, wrapping itself so tightly that it seemed to have shrunk a whole circle.

Anthony took out his key, ignored the crying ghost ("The one with glasses—the four-eyed dog—"), and opened the door to his office.

Most of the items on the table had been knocked to the floor, and an unfinished cup of tea had left a half-dried stain on the floorboards. The table, magically reinforced by the house-elves, was covered in scratches, and the cat's favorite climbing frame was lying on the ground. The curtains had been roughly torn open and were swaying gently in the breeze from the slightly open window.

Anthony sighed.

"Hello?" he called out. "Cat, are you there?"

A porcelain tray hanging precariously from the edge of the table wobbled, fell with a clatter, and shattered on the floor.

"Great, just great..." Anthony muttered tiredly, taking out his wand and pointing it at the broken tray, which reassembled itself before his eyes. He then began to tidy up the room bit by bit with his wand.

A little mouse darted out from somewhere, hurriedly scrambled up his clothes, and finally settled into his pocket.

At that moment, the cat sauntered out of the bedroom, tail held high, watching with pride as Anthony levitated an inkwell.

"I thought you were getting along quite happily," Anthony remarked to the cat. "There's no need to be so angry."

The cat meowed, rubbed casually against his legs, then immediately jumped onto the climbing frame after he set it upright again.

…

After Anthony finished cleaning up the mess and went to wash up, the little mouse and the cat lay down together, snuggled up affectionately. He shook his head, still puzzled by the curious relationship between the two.

He closed the window, drew the repaired curtains, and returned to the bedroom. The bedroom was clean and tidy, just as it had been before he left.

Anthony slipped under the quilt and quickly fell asleep.

He didn't actually go out to catch students wandering the halls at night. A warning, he thought, should have been enough.

…

The next morning, he began to regret not going out. At the breakfast table, everyone was buzzing about one thing: Moaning Myrtle had helped Filch catch nine students on a nocturnal escapade the previous night.

Anthony carefully checked the names of the nine students. To his relief, they weren't all from the first group of practical activities. Only the Weasley twins were unfortunately on the list, and Anthony didn't think their night out had much to do with whether he had organized the event.

He glanced over at the Gryffindor table. One of the Weasley brothers was chatting with the girl who had taken everyone's photos the day before. The other was tilting his head to look at the photo in Angelina's hand while talking with her. They seemed completely unfazed by having been caught sneaking out.

Anthony took a piece of fried toast for himself. "Myrtle really wasn't in a good mood yesterday."

"I think 'furious' would be a more accurate word," Professor Flitwick said, pouring himself a plateful of jam. "She claimed someone insulted her. She suspected it was a student trying to sneak out at night, so she spent the whole night patrolling Hogwarts."

"Insult her?" Anthony asked, raising an eyebrow.

"Didn't you hear, Henry?" Professor Sprout leaned over Professor Flitwick's head, joining their conversation. "The poor ghost said that someone passed right through her without even noticing, and didn't apologize. Then Peeves came along to torment her, but Quirinus drove him off; and finally, she found a note on the bathroom floor filled with insults directed at her."

Professor Flitwick added, "She spent the entire day crying. I was told her wailing could be faintly heard even in the third-floor bathroom."

"Oh my goodness," Anthony said. "Did she find out who left the note?"

"No," Professor Sprout replied, shaking her head as she cut into her pancakes. "No one admitted to it. In fact, the students felt terribly wronged. They had hidden themselves in a locked classroom, thinking they wouldn't be found."

"They were all together when they were caught?" Anthony asked, surprised.

Professor Flitwick nodded and said sharply, "A group night-time excursion. It's the largest gathering for such an activity in the past thirty years."

"And what was the punishment?" Anthony couldn't help but ask.

"Points deducted," Professor Sprout pointed to the hourglass on the wall, "Ten points for each student."

Professor Flitwick leaned in and whispered to Anthony, "Minerva thinks that's too lenient."

Professor Sprout added, "Even Severus, surprisingly, agreed with her."

Anthony glanced at the hourglass. The gap between Slytherin's emeralds and the other houses had narrowed considerably. The nine students caught didn't include any from Slytherin. At the other end of the teachers' table, Snape was sullenly working through his fish steak, but the fact that he was at breakfast at all usually indicated he was in a decent mood.

Anthony shook his head. "What were those students doing when Myrtle caught them?"

"Something to do with water guns," Professor Sprout said. "Their stories are so inconsistent that none of them seem believable."

"Ah," Anthony said, focusing on covering his toast with bacon.

…

After finishing the last of his pumpkin juice, Anthony stood up, bade his colleagues goodbye, and walked out of the hall.

He planned to check if Tom and Jerry had demolished his office again. If everything was intact, he could focus on writing the summary report for the first group's practical activities today.

As he passed by the Ravenclaw table, Anthony noticed the Gryffindor girl who had distributed the photos was already standing there. He overheard a student holding a photo ask her, "Is it true? Did Weasley really go into the girls' bathroom on the second floor to fill the water gun?"

The Gryffindor girl was momentarily stunned but then replied confidently, "Of course not, they just accidentally hit Myrtle in the nose while testing out the water gun."

The Ravenclaw student asked curiously, "Did the water go through her?"

This time, the Gryffindor student seemed less certain. She looked up at the ceiling and decided, "Yeah, it went through."

"I knew it!" the Ravenclaw student exclaimed, poking his classmate who was eating pumpkin pie. "Did you hear that? Ghosts can't touch water."

"But Myrtle can make a big splash in the toilet!" the friend retorted after swallowing a mouthful of pie.

As they continued to debate why ghosts couldn't touch certain objects, Anthony was too far away to hear the rest. He had a feeling that the entire school would be buzzing about Myrtle today.

...

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