Dimension G25237T. Earth. New York State.

Riverside High School.

“Therefore, the derivative to 3x + 5 is 3. If you want to find the integration, it is 3/2*x^2 + 5x + C. The C is very important.”

In front of a class of 27, a math teacher in his thirties scanned his students before calling out a name.

“Caitlin. Can you enlighten us on how to solve for the derivative of lnx?”

“Uh…” Caitlin was a blonde girl. She wasn’t the best at math. After all, she wanted to be a fashion designer. As for why she’s here? Well, she blames her parents. “Can I phone a friend?”

The class giggled. The teacher shrugged before nodding. He should’ve known. “Sure.”

“Well, Katie.” Caitlin turned to her best friend. “Maybe help your best friend out?”

Beside her, Katie looked up from her legs. She casually wiped her hands on her jeans before quickly answering. “Yes Mr. Isaac. The answer is 1/x.” She turned to Caitlin and smiled. Confidence was in her eyes. “You’re welcome.”

“Nice job. Thank you, Katie.” Mr. Isaac nodded and gave out a small smile.

Caitlin sat back down and whispered a gentle thank you into Katie’s ears. The brunette shrugged. She has been with Caitlin ever since elementary school. Through the years they took classes together, Katie was always the smart one.

“Going to question 23...”

But just before he could go on, Mr. Isaac’s eyes suddenly turned bloody red. He collapsed on the ground and started screaming. The students looked at each other in horror, wondering what to do.

“Oh my god oh my god oh my god.” Katie could hear Caitlin screaming beside her.

Even the brunette herself was moved. But as she watched the familiar man squeal in pain, she suddenly felt something from the deepest end of her heart. It wasn’t fear. It wasn’t anger. It was...excitement?

What the hell? Her teacher was getting killed by some sort of illness, and she was thrilled? What is wrong with her?

“Someone call 911!” Someone said. Immediately, half the school took their phones out and started typing. But none of their calls went through.

“Shit!” Caitlin cursed as she failed to reach the police. She checked her service and realized it was perfectly fine.

A couple of students ran to the door, only to find it locked. They did their best to break through to get help by smashing at the door repeatedly.

But it turned out help wasn’t required.

Mr. Isaac suddenly stood back up, but everyone could tell something was very wrong with him.

The math teacher suddenly glared at each and every one of them.

“You’re all going to die here.”

Katie knew she should be frightened. After all, what was going on looked like the opening credit of a supernatural episode, and everyone knows the people in the open credits never live long. But instead, she felt intrigued.

“Is that a Resident Evil reference?”

Bad timing.

Everyone stared at Katie before Mr. Isaac dragged the attention back by throwing himself out of the window.

The classroom was on the third floor.

The school building was surrounded by concrete floor.

Anyone with some common sense knows what would happen, and it ain’t pretty.

While most students froze in their seats, possibly peeing themselves, Katie stood up. She should be vomiting, but she could feel herself looking forward to what would be on the ground.

She had never seen a body in real life before...at this height, Mr. Isaac’s head should be in pieces…she has heard people referring to broken heads as exploded watermelons. She looked forward to making the comparison herself.

“Katie!” Caitlin yelled in fear, but Katie wasn’t listening. She walked to the window and peeked out, and saw nothing.

There was no blood on the ground. No body. She looked even further and still saw nothing.

The bell rang, signaling the end of the class. A student at the door pulled on the door again and managed to open it, somehow. The entire class poured out, screaming and yelling. Katie walked back to Caitlin, who was shaking from top to bottom.

“There’s no body.” She stated thoughtfully. “I don’t know how it’s possible. It’s the third floor. The fall must’ve killed him. But there’s no body.” She suddenly reached inside her bag and pulled out a pen, took the lid off, and jammed it into her palm. “Did someone remove the body? But...it’s impossible. This is very interesting...”

“Katie!” Caitlin looked at her friend like she was a complete stranger. “What are you talking about...what are you doing? Are you self harming?”

“What?” Katie looked down on her bleeding palm. She should’ve hidden it. “Hmm...not really. Anyways, it’s time for lunch.”

“Lunch…” Caitlin coughed. “Do you still have the appetite?”

“Of course.” Katie put the pen back into her bag. A hint of disappointment was in her eyes. “Why not?”

“No! I’m serious! Mr. Isaac jumped off the building!”

“Who’s Mr. Isaac?”

In the cafeteria, Katie bought a big lunch and sat down beside Caitlin, who didn't buy a thing. As Katie ate, the two started hearing the students from their class talking to the others about what happened, but things weren’t exactly right…

“It’s almost like no one remembers Mr. Isaac. He teaches three classes a day, but no one remembers him. How’s that possible? Did everyone suddenly get their memories wiped?”

“Is that even possible?” Caitlin frowned. She glanced at Katie, who was enjoying a hot dog. “We should call the police...”

“If students in this school don’t remember him, then why would the police?”

“At least the police have files and access to surveillance footages…”

“Where’s the fun in that?”

“I’m sorry?” Caitlin snapped around. “Do you think this is funny? You know what? That Resident Evil reference was very inappropriate. Our teacher just killed himself! The man probably had some sort of mental illness or something!”

“I’m sorry. I’m sorry.” Katie suddenly felt very guilty of what she said. Caitlin’s right. What happened was a tragedy. A life was lost. Even if, for some reason, her brain got a sickening kick because of the death, she should show some respect. “I’m sincerely sorry. I shouldn’t have said that.”

“It’s fine.” Caitlin’s heart went soft again as she glanced at Katie’s palm and suddenly remembered something very important. “Katie, I need to ask you something very serious. Are you self harming?”

Katie gulped. “It’s complicated.”

“If you are, you need to find help. I have read an article about how self harming is a way to cope with your problems. It’s also highly addictive. You need to seek professional help as soon as possible if you’re really doing that. It’s not good for you.”

“I don’t have problems I’m trying to cope with. I have parents that love me. My family’s not poor. I have you, my best friend in the world. I’m probably among the top 10% in the school academically. What problem do I have that I need to cope with?”

“Well, maybe stress? I don’t know. Why do you cut yourself?”

Katie went quiet as she thought about the question herself. She started to find fun in poking and jabbing at herself with sharp objects since a few years ago. Most of the times, it was just because she was terribly bored. Other times, it was to distract herself from awkward situations.

Maybe Caitlin was right.

“Fine. Whatever reason I did that for, I’ll stop.”

“Pinkie promise?” Caitlin held her pinkie out.

Katie sighed. How old are they? 6? But she still held her hand out.

“Pinkie promise.”

There was another math class after lunch. Only a portion of the students went to the classroom. The rest were gone, likely seeking help from more outside sources.

“Is anyone else seeing this?” One of the students spoke up in the half vacant classroom. “I talked to three of my friends, two of them were in Mr. Isaac’s class in different periods. They said they have never seen Mr. Isaac before. When I asked them who their teacher was, they said they didn't know and then just moved on like nothing happened!”

“Yeah, me too!”

“Same!”

Most of the students agreed. It seemed like they have had a similar experience more or less.

“Did someone call the police?”

“I did. It’s the same thing with them. They thought I was doing some sort of prank.”

“Well, we need to do something!” One of the girls suddenly snapped. “A man just committed suicide in a horror movie style! This is not right!”

In the back, Katie tapped her chin in boredom. The other students in the room were talking, but they weren’t speaking. Her eyes briefly landed on the pen in front of her, but she quickly looked away. She made a promise. She wasn’t going to break in this quickly.

“What happens now?” The brunette heard Caitlin ask beside her. “Are we going to have a new teacher or something? Or are we just gonna sit here for the whole class? What’s gonna happen to us?”

Suddenly, the door opened. Most of the students didn't turn, but the few that did froze.

“What the fucking hell…”

“Oh my god…”

“Uh...guys?”

Katie turned at the door, and she saw something that was very wrong.

Mr. Isaac was standing there like the beginning of any other class. Half his head was gone, and thick, dark blood quickly formed a puddle below him. He lost one eye, but that didn't stop him from staring at the students with his remaining one.

Katie heard Caitlin scream. She herself, on the other hand, felt a strange sense of excitement.

It was as if a rock broke the peace of a silent pond. The girl found herself grinning a little, but that shook her even more than the undead teacher.

What the hell is wrong with her?

Mr. Isaac made his way to the front of the classroom like nothing happened. He looked at the class.

“Can everyone please take a seat? I’ll be taking attendance soon.”

Some of the students that were previously standing slowly made their way to their seats. Katie could see some of them were trying to cover small parts of wet spots on their pants.

“It looks like some of the class isn’t here. Anyone know where they are?”

It was a simple question, but most of the class kept their mouth shut. The question was fine. The one that asked it was not.

Sensing the lack of answer, Mr. Isaac smirked coldly.

“Well, in that case, those students are late. As the teacher, it is my duty to punish them…”

“Shouldn’t you give them a chance first?” Katie suddenly spoke up. “We can call them and tell them to come back. There’s no reason to get all serious all of a sudden.”

What in the hell are you doing? Even as she spoke, Katie was screaming at herself inside. Standing up and challenging someone who’s either an undead or a zombie? That’s a one way ticket to hell in any horror movie. Why would she possibly do this.

The answer was simple.

She wanted to see how Mr. Isaac would react.

Mr. Isaac stared at Katie for two seconds before suddenly leaping to in front of her. The girl was surprised herself as she didn't even flinch. Instead, she looked straight at the opening on Mr. Isaac and did her best to suppress the urge to poke into it.

What does human brain fluid taste like?

“Very nice point, Katie.” Mr. Isaac finally spoke quietly. “I knew you are the bravest person in the class.”

Katie gave a small grin as the other students snapped out their phones as quickly as possible and started calling their friends. Immediately, the room was filled with shaking voices. Caitlin took out her iPhone X and started calling one of her friends.

“Jessica, please! Pickup! Pickup!”

Meanwhile, Katie rolled her tongue in her mouth before suddenly asking a question.

“What does it feel like to have your brain cracked open?”

Mr. Isaac stared back at her.

“Do you want to try it?”

Katie seriously considered it for a moment.

“Nah. I can throw myself down a building anytime I want. This, this is more fun.”

“Haha.” Mr. Isaac gave another bloodthirsty smile. “You’re right. We’re going to have so much fun together.”

Once again, Katie couldn’t help but smile. Her heart beat in excitement as she thought about what would happen next.

Ten minutes after all the calls ended, most of the students were back. They were paralyzed when they saw Mr. Isaac, and some tried to flee, but in the end they were all forced back into their seats.

“Jessica…” Caitlin was clutching to her teeth. She called Jessica, but her friend has decided to run home after the incident before lunch. It would take her more than ten minutes to get back here.

And time was running out.

Mr. Isaac stood up again. He snapped his fingers, and the door was shut.

“I have been very lenient, but some students are still tardy, and tardiness to this extent must be punished.”

4 students still weren’t in the room.

“Please!” Caitlin shouted in her seat. Her concern overcame her fear. “Jessica’s on the way back! Just give her a few more minutes.”

She turned to Katie, seeking for help. After all, Katie was the one that bought the first ten minutes. Maybe she could buy some more?

“It is a bit unfair for some students.” Katie spoke up halfheartedly. Her conscious told her to help save some of her fellow students from a likely unfortunate fate, but a growing part of her just wanted to see what the punishment would be. She took a deep breath and did her best to toss those foul thoughts out.

She knew Jessica as well. Jessica is a caring and compassionate person. Jessica didn't deserve to die to satisfy her own curiosity.

The next second Mr. Isaac walked to Katie, grabbed her by the throat, and slammed her on the table in front of her, hard.

“I like you, Katie, but don’t overstep it.” He warned before walking back.

Caitlin’s eyes widened as she got up and helped Katie get back into her seat, all the while whispering apologies. If she didn't ask Katie to speak up, this wouldn’t happen. But Katie wasn't listening to her friend’s words. Rather, she touched her aching back.

That felt really good. The thrill. The pain. The fact that she had no knowledge of what would happen.

Meanwhile, Mr. Isaac went back to his teaching. He snapped his finger. For a moment, nothing happened. But as the students sat there, waiting, the door opened and one of the four students walked in.

“Carl!” One of the students shouted out in relief, but Carl didn't look at him. Rather, he walked to in front of Mr. Isaac and froze there.

Three students entered within the next five minutes. Jessica was one of them. All of them formed a line in the front of the classroom. They were expressionless.

Mr. Isaac faced the entire class.

“Well, I gave them a chance, and they didn't take it. As a result, they will be punished...by death.”

The class gasped. Except for the four, of course.

“Don’t do this!” One of the boys shouted. He was Jessica’s boyfriend. The two were really close. He tried to stand up, but all Mr. Isaac did was glance at him, and he was literally fixed to his seat.

There was nothing he could do but watch the events unfold.

Mr. Isaac turned to the four students and smirked.

“I always like hearing from you, even now.”

With that, the four students suddenly realized they could talk. Unfortunately, that was all they could do. They started shouting and crying and begging, but nothing worked.

“Proceed.” Mr. Isaac said again.

It was the last strike.

The four students walked to their desks. Even though they could talk, they didn't have any control over the rest of their body parts. They opened their bags and pulled out sharp tools, like pens and scissors.

The entire process was involuntarily done.

“No!” Caitlin screamed as she realized what would happen.

The screams from the four students grew louder, but their screams failed to stop the inevitable. They didn't even manage to delay it.

Simultaneously, the four students jammed the blades into their eye sockets and continued to push them in. They screamed, but that was all they could do. Their hands continued to push the blades in with full strength until the blades reached their brains. Finally, the four students were put out of their misery.

The whole process took five minutes.

Four down.

Twenty three left.

And the game has just begun.