A book and a pen suddenly appeared in his hand. He copied all the parts about flesh and blood Alchemy from "Forbidden Alchemy", then put "Forbidden Alchemy" back on the bookshelf, picked up his handwritten copy, and was about to head back.
On the way from the Library to his office, Kaisen suddenly heard a series of footsteps, as if someone was running away.
He didn't say anything about it; Filch catching Little Wizards out at night was nothing new.
It wasn't until he had walked nearly twenty meters from that staircase that he realized the classroom at the top of that staircase seemed to be the one Dumbledore used for fishing.
And that classroom also housed Hagrid's Cerberus.
"Oh, my Merlin!"
An ender pearl instantly appeared in Kaisen's hand. In just three breaths, he appeared outside the classroom door.
He quickly pushed the door open and saw four Little Wizards.
At the same time, a bright light came from a distance, accompanied by a breathless voice.
"Is that Professor Hiss? Did you see four Little Wizards out after curfew?"
Kaisen looked down at the four Little Wizards squatting in front of him, shaking their heads frantically, and then at Filch holding a lantern not far away. He still shook his head.
"Is that so? I'll go check the other floors then! Those naughty little rascals, they can't escape my grasp!" Filch said sinisterly as he walked towards the staircase.
After Kaisen confirmed Filch had left, he quickly lifted all four Little Wizards out of the room, one in each hand, in two swift moves.
"Harry, Neville, Ron, Hermione, tell me, why were you out after curfew? No, compared to that, being out after curfew is a trivial matter. Do you know that this big fellow only needs two moves to eat three of you?"
"And the last one would even be divided into three pieces!"
Kaisen brought the four Little Wizards back to his office and immediately reprimanded them sternly.
"It was Malfoy, he challenged us to a duel, but then he ran away and snitched to Filch. We were afraid of losing points..." Ron said, feeling a bit wronged.
"It's just points, so let Filch deduct them! Didn't Dumbledore say at the beginning of the term that that empty classroom was dangerous? Did you just ignore it?"
"Is losing points better, or losing your life? At worst, he'd just give you detention. Is death more acceptable than detention?" Kaisen straightened up again, hands on his hips, continuously lecturing them.
"If it's Snape's detention, then it really is worse than..."
"Harry, shut up! You haven't recognized the seriousness of this matter yet!"
"You misjudged the danger level of the two outcomes. Before you hid in that classroom, you should have thought of Dumbledore's warning at the start of the term. Alright, perhaps you panicked and didn't react, that's fine, but when you saw that Cerberus, why didn't you escape immediately?"
"Do you really think that big dog was sleeping soundly? Even if I didn't say it, you should have been able to see clearly that if that big dog really attacked you, Harry, Neville, and Ron would be swallowed in one bite each, and Hermione, the last one, would be the most miserable because you'd be bitten into three pieces!"
The more Kaisen spoke, the angrier he became. Just that evening, he and Snape had gone to install Potions in the piston door's Potion launcher.
And for an adult Wizard like Snape, Kaisen clearly saw a layer of silver light flash over him before he entered, which should have been a Shield Charm, yet even that was breached by the Cerberus.
What was even more frightening was that Kaisen later knocked the Cerberus unconscious. Unconsciousness and sleep are seamlessly connected, meaning the Cerberus hadn't eaten dinner.
If, while the four of them were hiding, the Cerberus groggily woke up and then found three main courses and a snack...
"You... fine, you'll lose points. No, I'm also a Professor, I'll deduct points directly from you. Four Gryffindor students, twenty points off each!"
The four Little Wizards all hung their heads. For the first time, they felt that Professor Kaisen, who was usually as gentle as a little sun, was so frightening when he got angry.
His furious aura was no less than Professor McGonagall's, and his sharp tongue was no inferior to Snape's.
However, one sensitive Little Wizards noticed a hint of a different emotion beneath the raging anger.
"S-sorry, Professor." Neville said, his head down, his voice a little choked up.
"Neville... er... Neville!"
Kaisen instinctively wanted to squat down to comfort him, but he quickly realized he still needed to be serious, serious, and even more serious!
"Do you know your mistake?"
"Yes..."
"What do you know?"
"We shouldn't have gone to that classroom."
"Besides that, you failed to see the situation clearly. Couldn't you use your brains to weigh the options: losing points versus death? Which is more terrifying?"
"Yes, Professor, yes."
"And you can't harbor that kind of Luck mentality anymore. I knocked that dog out this afternoon. You couldn't have been sure just now whether it was asleep or unconscious. What if it woke up, or woke up hungry...?"
"Neville... Neville?"
Kaisen saw a small puddle appear on the floor beneath Neville's feet and sighed directly, hands on his hips.
"Never mind, you should already understand the seriousness of this matter."
"Mmm."
"Also, what have you learned from this incident...?"
"Next time, when something happens, weigh the pros and cons... although that sounds like Slytherin..." The first part was said by all four together, the latter by Ron alone in a whisper.
"The traits of all four houses are strengths. You can't ignore or even discard the strengths of Slytherin just because you dislike Slytherin," Kaisen added.
"We will, Professor."
"Alright, now all of you go back. Walk straight to your dorms." Kaisen said, pointing towards the door, which opened with a creak.
"Never mind, I still don't quite trust you. After all, you are Gryffindor. I'll escort you back."
"Professor, you don't have to." Neville said, looking at Kaisen with reddened eyes.
"Just consider it me helping you avoid Filch."
The five remained silent the entire way until they reached Gryffindor Tower. After watching all four disappear into the stone archway behind the Fat Lady, Kaisen's formerly serious face finally relaxed.
"Being serious is truly exhausting. I wonder how Severus maintains it twenty-four hours a day... And my flesh and blood Alchemy, a full two hours... Filch was right, these Little Wizards are indeed a bit too naughty..."
"The Little Wizards of Gryffindor are also a bit thoughtless."
Kaisen muttered to himself as he walked back to his office.