The air was getting colder. Cohen was starting to drain her positive emotions.
Umbridge's fiery bluster was plummeting. She had realized that Cohen was showing the claws of a hybrid monster, and the bone-deep chill was forcing her to instinctively use the Patronus Charm.
"Expecto Patronum!"
She used the last of her happiness to summon her silver cat Patronus, and when she saw Cohen's brow furrow slightly, she thought he was just a clueless little half-blood who'd never seen a Patronus before, an upstart who thought he could get away with anything just because he was some sort of half-Dementor. She was about to sneer triumphantly—
"Expecto Patronum."
A gigantic, silver Dementor with long, skeletal hands wrapped its grip around the silver cat's neck. In an instant, the cat dissolved into a wisp of smoke and was devoured by the Dementor.
If it had been a normal Patronus, it might have been able to put up a fight against Cohen's, but unfortunately, the happiness Umbridge used to summon it was far too meager.
It wasn't just the Patronus; Umbridge herself was no match. Her soul strength of a mere twenty-something posed no threat to Cohen.
"You... you can't kill me!" Umbridge shrieked, her bravado failing her. "I am the Senior Undersecretary to the Minister of Magic, the Hogwarts High Inquisitor, and the Defense Against the Dark Arts professor—if you dare lay a hand on me—"
"This room isn't big enough for all those people," Cohen said ominously. "But you'd be delusional to think you'll die right away. Only enemies I'm not disgusted by get to have it so easy..."
A hint of color returned to Umbridge's face. She thought her words had made Cohen afraid.
He was afraid of the Ministry's retribution...
"I'm going to turn you into the thing you despise most," Cohen whispered. "A Muggle? A harpy with pieces of other animals? Just imagine Fudge seeing that you're actually that sort of creature..."
"No, you can't do that, you can't change—you lying half-breed!" Umbridge spat through clenched teeth. "You can't do this to me... As soon as Cornelius knows all about this—Agh..."
"And what will he do when he finds out?" Cohen asked amiably. "What do I have to be afraid of? A Minister who's about to be ousted, and his lunatic, monster underlings? Or a government filled with lies and Dementor fodder? Don't worry, you'll be alive for a little while, until one sentence is carved deeply into your heart—'I must not tell lies.'"
Umbridge shrieked in pain.
Words, as if carved with a knife, began to appear on her hand.
I must not tell lies.
Then, the wound healed, only for the invisible knife to carve the words again.
I must not tell lies.
Umbridge trembled, clenching her fists, her gaze still full of venom and hatred toward Cohen.
"It seems it's a bit difficult to carve that sentence into your heart, isn't it?" Cohen asked, a sunny smile on his face. "But don't worry, I have plenty of ways to make it stick."
---
Meanwhile, in the office, Harry was bored senseless, repeatedly writing the sentence. He had been listening intently for a while, but he couldn't hear what was happening in that little room. Finally, with nothing else to do, he started to write the toad's required phrase: "I must not tell lies."
The words looked like bright red blood, but Harry couldn't figure out where the ink that looked like blood was coming from.
Never mind—write it again.
Cohen still hadn't come out.
Write it again—
Still no sound.
Write it again—
...
Write it again—
Bang!
Behind Harry, the office door was slammed open, but Harry saw nothing. The hallway outside was empty.
Then, the door clicked shut again.
Harry instantly jumped up.
"Who's there?"
"Don't worry, little one, I'm just delivering something to my grandson," the invisible old water serpent said happily.
"What?" Harry was stunned for a moment, then he remembered the horned water serpent in Cohen's box.
What was Cohen planning to do? Why had he even called the water serpent?
The bedroom door opened a crack, and Harry could see something thick and snake-like slither inside. Harry watched the door close again, and then all was quiet.
Puzzled, Harry couldn't help but let his mind race.
What was the old water serpent delivering to Cohen?
Why had Cohen and the toad been in that room for so long? What if Cohen... killed her?
The thought of the pink toad being dead brought Harry a twisted sense of satisfaction, but if Cohen had actually killed someone from the Ministry...
The more he thought about it, the more worried he became for Cohen.
...
Meanwhile, inside Umbridge's room.
"My darling grandson! I've brought you that thing you asked for!" the old water serpent announced gleefully, dropping its invisibility. Wrapped around its tail was Cohen's flesh-and-blood puppet, which still looked like Voldemort; Cohen had retrieved it from him at Malfoy Manor. "Hey, isn't that the witch who scared the little one? Is she dead?"
The old water serpent looked at Umbridge, who was lying on the floor, and asked Cohen.
He sounded a little disappointed—he had wanted to bite her a few times to get revenge for the little one.
"She's not dead," Cohen said. "Just bite her for a bit first. I've got something big to do later."
This "big thing" was not unfamiliar to Cohen. Last semester, he had helped Sissoko and the others temporarily switch bodies.
After receiving Cohen's instruction to "just bite her," the old water serpent immediately bared its two rows of sharp fangs. Unlike a basilisk, its bites left two neat rows of marks, and it could rip and tear with a shake of its head.
All Cohen had to do was extract her soul before she died completely.
After being hit by Cohen's petrification spell, Umbridge was thrown around like a grotesque ragdoll by the old water serpent, the blood from her tearing wounds splattering everywhere on the floor.
Meanwhile, Cohen was busy adjusting the appearance of the flesh-and-blood puppet, making sure its "first phase" looked exactly like Umbridge.
As for the creature's second phase...
That was a sight to be revealed during the next Defense Against the Dark Arts class.
After Cohen had finished modifying the flesh-and-blood puppet, the old water serpent tossed Umbridge onto the ground, and Cohen transferred her soul into the puppet.
"Hiss—my teeth feel a little loose—I think I need to get new ones..." the old water serpent said.
...
Harry was still lost in his thoughts.
But a moment later, Cohen came out.
"Why are you still here?" Cohen asked in surprise. "Aren't you going back to finish your homework tonight?"
"I just heard the horned water serpent's voice—he said he was delivering something to you—"
"Yes, I did ask him to bring something for me," Cohen said, then hissed at the now-invisible old water serpent beside him, telling it to go home.
"What about Umbridge?" Harry asked, looking toward the bedroom. "What happened in there?"
"I ran into some of the 'toad's little secrets,'" Cohen said mysteriously. "You'll find out in our next Defense Against the Dark Arts class."