A huge shock wave arose as the students were alarmed by the sudden land motion, they turned to the window and saw the shed was blasted by something or someone.

They saw Koro-sensei was ragged as someone escaped the pitfall below and landed on the roof, on top of the roof stood a long, green colored haired girl with tentacles attached on the back of her neck.

Everyone was surprised by the sudden appearance of Kayano, they didn't expect her to have an tentacles.

"Aw, I attacked at my best...I can't believe I let him get away, I underestimated him."

The Kayano Kaede they knew finally dropped her act and showed the real her in front of everyone.

"Kayano, what in the world..?" Koro-sensei asked.

"Sorry, Kayano Kaede is not my real name—I'm Yukimura Aguri's little sister...you get it, Murderer?" Kayano stated.

Everyone was shocked as the name Yukimura Aguri was the name of their homeroom teacher before Koro-sensei even came to this classroom.

"I've heard that your parents were killed by the hands of an assassin, and then you came here to seek revenge for them, Angel?" Kayano said as the others turned to her, her red orbs widened in that information that she obtained.

"How...did you know?" she asked, surprised.

Kayano smirked at her hopeless reaction, how cruel her face is.

"Soraru-san mentioned the killer to me the other day, if my memory serves me right, the name of the killer is...called by the name Koro-sensei?"

Angel's eyes widened even more as she knew that Soraru came to their classroom just to tell her that, then Kayano laughed hysterically.

"What a coincidence! The people that we care about were killed by that murderer!" Kayano grinned devilishly.

"...Y-You don't know that for sure! Koro-sensei might not be the one who pulled the trigger, there's no way!" Angel protested.

"Your parents were killed since you were six years old, that means nine years has passed since then...I bet around that time Koro-sensei was still a human back then." she stated.

'W-Why did Rin told her about that? I trusted her not to say anything!'

Kayano held out her hand with a smirk on her adorning face, that's when Angel realized that she really did finally stopped acting.

"Join forces with me Yuuki Angel. Together, we can kill Koro-sensei."

Angel adverted her gaze with her while biting her lower lip, she didn't want any of them to find out her secret, her dark past.

"I-I....um...Kaede...you see..."

"Why are you hesitating for? He took the lives of your parents, don't you want to get your revenge for them?!"

The green head noticed her lips quivering while her knees were wobbling, she sighed.

"Never mind. Koro-sensei? I'll keep killing you, I'll let you know the place beforehand." Kayano said as she turned to their sonic octopus who was wounded.

"Now that I've fought you, I know for sure...I can kill you on my own now." she used her tentacles to escape the place swift fully as the others watched her leave quietly.

"Unthinkable, if she grew tentacles without maintenance, she would have been under constant hellish pain..."

"Not only that, but she's Yukimura Aguri's little sister?"

"Isn't that our old homeroom teacher?"

"I thought I'd seen Kayano before somewhere, do you remember Mase Haruna, the young prodigy who could take any role so easily."

"It's been awhile since she left the entertainment world, her appearance is so different so I didn't notice."

Which is the real her? that was what everyone was thinking about.

✦ ✧ ✦

"There was someone unexpected in the classroom other than Yuuki Angel when I first entered." a man in white clothing said to the person who was interrogating him.

"Yukimura Aguri's little sister, her real name is Yukimura Akari, she went inside the classroom with the name Kayano Kaede which was a false." he stood up, placing the information sheets on the table.

"As expected, she has the tentacles, understanding how it worked and used she knew all of it in a short amount of time...what a kid!" he was amused in how smart Yukimura Akari was.

"Yukimura Akari has a mental strength while Yuuki Angel has a physical strength...if those two team up with each other, the chances of killing Koro-sensei will raise to bounds and leaps dramatically!"

There talents for assassination are head and shoulders above everyone.

✦ ✧ ✦

After Kayano Kaede's escapade from the assassination classroom, she switched her outfit to another dress as she stared at the city's outskirts alone.

Flash back

This was before Yukimura Aguri's death and Koro-sensei official appearance in the classroom, Akari finally had the time to rest after a long day of working.

"Maybe I should get regular jobs for a chance?" Akari said as her black, curly hair reached her back, then a sudden explosion came to the facility that she is trying to reach.

Caught in the explosion, she walked in the wrecked place, thanks to her small body, she was able to crawl through the falling debris faster than the adults can.

Her eyes met the sight of her sister, Aguri, who was laying on the cold, hard cemented ground, beside her was an unknown monster whose tentacles were in amok.

"Onee-chan...?"

She walked up to her while her eyes widened, she tried to wake her up, she shook her shoulders but no avail. She reached for her pulse to feel it not pounding, that's when she realized the cruel fate.

She was dead.

Tears rolled down her cheeks as she saw a note next to her sister's body, her eyes widened as she silently read it.

To whom it may concern, I will withdraw for now but, I can take over as the homeroom teacher for Kunugigaoka Junior High Class 3-E if you want. I will discuss this with you at a later date.

From a super-destructive being

After reading the letter, next to her sat lots of vials of liquid, she found out later that they were tentacle seeds, she took one with her.

She knew that she will need it if she's going against to that monster that she hasn't seen before, shortly afterwards, she researched for how it works on her own.

Human-Tentacle Weapon Prototype

She found it in one of her thesis, it was the type that can be implanted into human beings, but they will undergo hellish pain if maintenance was neglected.

She knew that, and she took the risk just for her sister's revenge, once she put it on her mind, she keeps rolling until she succeeds.

"Congratulations for being admitted in this school, Kayano Kaede."

"Thank you very much!"

That time, she had her same hairstyle except her green colored hair though, it was black.

"I heard that there's a class for students with delinquent behaviors in this school—right?"

She inflicted harm on one of the principal's items, causing her to move to the Class 3-E the next day.

✦ ✧ ✦

"You're so lucky that you're cute, Akari! I'm jealous that you got those genes and I didn't." Aguri said while laughing.

They were at the cafe, hanging out together as siblings, Akari was secretly jealous of her sister too, for having such a huge rack when she doesn't have any of them.

"The only thing we have in common is our black hair, huh?"

✦ ✧ ✦

Then the scenario changed once again, she entered the classroom with green hair and cat style hair in fashioned.

"Oh, you must be...?"

"Yup, I transferred here today."

Kayano put down her bag as Nagisa looked at her, back then, he had long blue hair tied with a strap, there was a red stains on his cheeks.

"Your hair sure is long."

"Oh, I want to cut it short, but there are reasons why I can't."

Then Kayano realized that she'll be watched as she tried her best to hide her blood lust, so she created Nagisa as her main character and devoted herself as the side character.

"Look, you're the same as me now! I'm Kayano Kaede, nice to meet you fellow classmate!"

There was once a time that the tentacles asked her what she wanted to be, and her answer was.

"I want to be an assassin."

That memory replayed on her hair as she didn't care if she dies as long as she gets her revenge.

Then she remembered a certain girl's words played in her mind:

"I can die anytime y'know, but before that...I'll surely complete my mission first. If I don't, it's like everything I've done until now is a piece of trash."

Honestly, Kayano admired that girl before, she was brave, strong, and kindhearted. At first, she didn't knew why someone like her even became an assassin.

Not until when Soraru Rin mentioned that to her, it was during the time when the pink head came in their classroom and threaten them that there was a bomb planted everywhere.

She came to help Angel who was in pinch that time, that's when Soraru told her the killer of her parents.

"As I thought, you don't follow directions. I even warned you to wait until my preparations were done." someone spoke behind her, breaking her from her own monologue.

"What do you think you can do? You couldn't even take care of Itona-kun and abandoned him."

"From the looks of it, your metabolic balance is off as well. The fate of ones using untamed tentacles—"

Kayono launched her tentacles at Shiro who dodged it just in time.

"Mind your own business, I'm going to kill him myself. Don't bother me." she sternly said as Shiro sighed.

"So, did you got that girl to side up with you? Y'know...Yuuki Angel?" he asked.

"No, but I bet she'll change her mind and join me in the fray eventually." she grinned.

"It is rather assuring to have her on your side, do your best and pull her." he stated.

"...No need to remind me that." she scoffed in reply.

Kayano escaped once more as Shiro chuckled in how cold her little sister is to his only big brother.

✦ ✧ ✦

Back in the classroom, they saw the real Kayano Kaede who was acting in one of her shows, they finally knew how she was able to hide her identity.

She was acting as the cheerful, fun, and almost harmless Kayano Kaede.

"Koro-sensei, Kayano called you a murderer, what happened?"

"We've built up trust with you for so long now, we won't doubt you."

"Same goes with you Angel, what does Kayano mean by earlier?"

"All of us trust you both but you have to tell us about your past."

"If you two don't, no one will be able to accept the current situation."

"That's how all of us feel right now."

Koro-sensei maintained his usual smile, but deep down they knew that he wasn't really happy and smiling. Angel lowered her head down as shadows appeared near her eyes, she didn't wanted to let anyone know her past or even remember it.

"Very well, I'll tell you everything about my past. That's if we're all complete, right now, we're missing Kayano-san who is a member in this class as well." Koro-sensei said as the students nodded, all of them now turned to Angel who was still lowering her head down on the floor.

"...I'm going home now." she said as her voice was cracking, the class was shocked as she grabbed her things and left the classroom, the others tried to stop her when their teacher spoke.

"Let her be for the meantime, she has a dark past of her own...right now, she's stuck in the darkness with no one to give her light. I bet that's how she's been living all this time."

"I hope she does open up to us."

"Yeah, Angel has been really kind to all of us, and I hope she'll let us return her kindness back to her."

"She always finds a way to help us with our problems, so I wanted to do the same for her!"

Koro-sensei's heart was etching with depression and agony, he wanted to apologize for what he did.

"Sometimes the most broken people try to fix others because they cannot fix themselves..." Nagisa absentmindedly muttered as the others turned to him, then he waved his hand above his head.

"I-I'm just quoting my best friend!" he stuttered.

"I agree with Nagisa, I thought that Angel was a strong girl but...she was just a weak girl who hides her fears."

"Somehow, I feel sad for her."

"Same here."

Life without mysteries is dull, but the more mysterious ones past is, the more you wanted to hide it from the others.

The pain, the tears, the scars, the agony, the depression...you think about it.

Angel walked through an abandonment alleyway, at the outskirts of the town. Then an image flashed through her mind, that one time when she was standing in a pool of blood and dead bodies.

That traumatic flashback made her feel nauseous as she puked on the dark corner, sweat dripped on her forehead as tears filled her eyes.

"I can't drown my demons, they know how to swim." she said.

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EDITED ON APRIL 30, 2017
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