The XO class was in the chemistry lab for their chemistry class with Miss Boa. They were to conduct an experiment that day. As usual, the students were in pairing of girl and boy since the amount of each gender balance each other, which didn’t helped almost all of them who hated each other’s guts.

The warning Miss Boa got from fellow teachers when they found out that she’ll be conducting experiment with class XO was playing in her mind like a broken record. It didn’t make sense to her how scared the other teachers were about her safety doing an experiment with a bunch of teenagers.

Oh how naïve this new teacher is. Miss Boa is a new teacher in SM High. She recently changed from a school in Busan to SM High last week and this will be the first time she’s going to teach class XO. What she didn’t know is that the last time class XO did an experiments, the whole lab was burnt because of a prank Chen did to get to Minri. It’s why the other teachers warned her when they heard about the experiment. For all they know, maybe this time the lab will explode because of Minri’s prank.

Miss Boa just sighed and hoped that all went well for her that day. “Alright class, today’s experiment is going to be tricky so follow my instruction carefully as to avoid any mishap. Am I clear?”

“Yes, Miss!” the whole class answered in unison.

Minri looked to her left side and saw her partner for the day was Suho. Instantly, she light up because it looks like thing was going to be good for her since Suho is the type to focus on his work and he’s not going to notice her disappearance. She then looked around for her target and she smirked when she saw him at the back with Eunmi, the troublemaker of XOXO. Really, things keep getting better for her that day.

Liz who was already bored by the lesson let her partner, Luhan do all the listening and she looked around the lab for something interesting when she saw Minri smirking by herself. She smiled and went to Minri’s table like a happy puppy.

“Ehey I see you smirking. Bet something good about to happen?”

A devil smile appeared on Minri’s lip, “Remember last month Jongdae set the lab on fire and I got third degree burn on my legs?”

Liz shuddered at the memories of the burnt lab, “Wasn’t that a prank directed to you?”

“Yep and today a prank will be directed to him.”

“Oh this is going to be fun. Should I warn this to the others?” Liz said excited that the epitome of all evilness is about to do something for the day.

“Yeah you do that, don’t want them to get hurt in the way if something big happen. Call Eunmi here whilst you’re at it.” Minri said, smirking and patting Liz’s shoulder.

Liz just beamed and went away to do as told. She went to each one of the XOXO members to inform them beforehand of the prankster of the group’s plan. Jaemin and Hui Yi gave Minri disapproval looks but she just shrugged at them while Vilsa stared at her with her face questioning her sanity. Whilst for the others, some shook their head already used with her random prank and some were actually anticipating her plan.

Eunmi came to her table right after Liz told her to. “I take it that you’re going to need my help?” She asked with a sneaky smile.

“Right all I want you to do is distract Jongdae whilst my plan is in motion. Easy enough for you?” Minri replied.

“What do I get?” Eunmi asked, testing her luck.

“The joy of seeing EXO suffering. That enough for ya?” Minri inquired with a raised of an eyebrow, daring the maknae to ask more than that.

Eunmi chuckled, seemingly getting the meaning of it. “Alright seems good enough. Bye.” She waved and went back to her table.

Minri dug around her backpack for something. She has read something really cool on the internet and conveniently it has something to do with the thing she likes.

The thing about Minri is that she really, really, really loves mint flavoured food and drinks. She really loves Mentos in particular. She carries those candy at least 4 packets in her bag and that’s what exactly she was looking for in her bag. And that day, she brought over more than a hundred package of it. Once she found what she’s looking for, she went to the back of the lab where a fridge was placed.

She began to put a piece of mentos in each ice cube container until none of all 10 batch is left empty and pour water over it to make ice cubes. While waiting for the ‘bomb’ to frost, Minri made way to each table of the lab and put the stopper in the sink at the middle of each table. EXO members just eyed her, afraid something will happen to them as they knew Minri is the female version of Chen. But when all she did was to bother the stopper, they let it go without much thinking.

Minri went back to her table and pull out her phone. She went to their group chat and typed in a message.

Minri_Choi : Can you guys like fill up the sink at your table until its half full?

Jaemin_Jung : Why would I cooperate with this one?

Hui Yi : I can tell this is going to end up real bad so no

Kelly: what is it this time?

Vilsa : tf are you thinking again?

Minri_Choi : Liz? Maknae line?

Wen_Lizzy : Done!

Eunmi_Cho : Me too!

Jay-yeah : Done!

Irisss : Did it!

Minri_Choi : Good job, children! (;

Minri_Choi : Gina? Nara?

Nara_JJANG : Did it ~

Gina : Idk unnie, you always pull off something dangerous and I’m afraid something bad will happen...

Minri_Choi : Oh Gina baby worry not, I decided to exclude you guys from this one so do as unnie said?

Gina : Okay...

Yerin_Ahn : We are excluded? Cool, done it.

Minri_Choi: So our four oldest unnie, you were saying?

Jaemin_Jung: Oh well might as well.

Hui Yi : Fine, whatever.

Kelly : You can’t be stop can you...

Vilsa : oh for sake whatever

Minri smiled in triumph. She went back to the fridge and was satisfied seeing the ice cubes is ready. Thank goodness for their richness and technologies that they could have their own fridge even in the chemistry lab and one that freeze ice in only 10 minutes.

She pulled out her phone once again to send a few final messages before proceeding with her plan.

Minri_Choi : Distract your partner please girls!

Minri_Choi : And when I yelled, “WHAT TIME IS IT?”

Minri_Choi : You guys are to run for your life from the lab okay

Yerin : Really? High School Musical reference?

Minri_Choi : Shut up Korean ver. of Sharpay I happened to like that movie and if you still wanna live then you better do as I said!

Vilsa: With you? Might as well be dead

Minri rolled her eyes at Vilsa’s replies and put her phone away. When she was positive the other XOXO members were doing as told, she gathered the ice cubes in a small bucket she got from who-knows-where and move like a ninja in the lab from one table to another.

Minri went to Chen & Eunmi’s table first and dropped about 50 ice cubes mentos into the sink half fill with water. She did the same with each table but with only 40 ice cubes mentos instead because only Chen deserves to be punished honestly and only 30 ice cubes mentos at her table because Suho is a nice guy and Minri pitied the poor guy that did their partner work all by himself.

Once done, Minri went to stand by the door ready to escape when the time comes and looked at her wristwatch. It’s a pity that Miss Boa is the type of teacher that loves to survey her student’s work because she might be getting the side effect of what will happen next and Minri could only hope that when the time comes, the teacher is not anywhere near Chen’s table or God forbid, the new teacher might get a trauma in her first week teaching at SM High especially this class. It was no wonder why so many teachers transferred out of SM High and each of them gave the same reason for leaving: Class XO.

Minri glanced at her wristwatch once again and knew it was time to go so she looked up, “Uh oh...” she said when she saw the teacher stopped at Chen’s table. “, whatever not my fault.” She said and took a deep breath before yelling, “WHAT TIME IS IT?” and took off without looking back.

She didn’t have to because she knew the girls got her message very clear and they did. As soon as Minri yelled the code, all of XO members bolted out of the lab leaving the EXO members and the new teacher bewildered at the odd scene.

“What the is happening?” Chen asked and as soon as the question left his mouth, the sink at his table exploded and Chen flew backwards from the explosion and hit the table behind him real hard. Water poured out continuously from the broken pipe, the result from the explosion.

Not much later than that, one by one the tables inside the lab exploded and each one of the guy flew backwards though not as hard as Chen did considering the amount of mentos cube in their sink is lesser than him. Except Suho that staggered backwards only and fell on his for his table got the least amount of mentos cubes and he immediately know that Minri decided to spare him a bit and he was grateful for it somehow.

And when they thought the now flooded with water and broken sink parts lab is done with the prank, the sink all around the lab including the teacher’s table- which is also equipped with sink- exploded too but with much bigger explosion than Chen’s table sending everyone right on the floor from the impact of the explosion. Blisters, splinters, smokes and broken part of the sink flew all around the lab.

They all squeezed their eyes shut and coughed out from the lacked of oxygen in the smoke-filled lab. Chen heaved himself into a sitting position, leaning against the board that kept the apparatus for experiment. “Dammit, damn.” He muttered at first then proceed with a yelled that startled the other members, “Its her. Its Minri I just knew it! DAMN IT MINRI!”

Xiumin went to Chen and gasped when he saw red liquid flowing down Chen’s face. “DAE you’re bleeding!”

As all of the sinks in the lab is broken, water flood the lab non-stop and before they knew it the water level has reach their knee. Miss Boa stood up, although a little dizzy and opened the door of the lab successfully letting the water flow out to the corridor.

Xiumin and Luhan both went to Chen and helped him get to his feet and dragged him out of the lab to the clinic. The other EXO members picked their selves up and went out of the lab and headed towards the same direction as the previous members.

Chanyeol let out a chuckled whilst walking, “, the pranks between them are getting out of hand now.”

“Its ing dangerous I swear the longer I spent time with the two of them the sooner I’m facing my death.” Kris spoke whilst limping, a part of the sink and the table smashed his leg during the explosion.

“No kidding, what in the world is Minri thinking? Trying to kill us? I know we all had some kind of past with them but really?” Baekhyun asked a bit bewildered at the situation happened.

“Can’t really blame her. Last month Chen set the lab on fire and she got a third degree burn.” Suho replied, trying to justify the girl being the angel he is.

D.O grimaced, “Yeah I think Minri is kind enough with this prank you know. The time Chen set the lab on fire, we all were involved in it. He didn’t even warn us. We could die too back then. At least Minri decided to spare her own members in this prank.”

Kai hummed, “We’re kinda in luck in this one. Seems pretty harmless compared to Chen hyung’s prank. The XOXO girls all ran for their lives after Minri yelled their code.”

“I think I might be getting a dimple on my left cheek courtesy of Minri’s prank today.” Lay joked around showing the guys his injured left cheek.

It wasn’t exactly funny but they laughed anyway as it has been quite the ride that day. Amongst the laughed, a horrified shriek came from the lab that sounds pretty much like their new chemistry teacher. They stared at each other before bursting in laugh yet again.

“Oh boy, pretty sure she’s gonna quit.” Sehun commented in between his laugh.

Tao wiped a tear from his excessive laugh, “It’s her first day teaching us and already she became a victim of our class.”

“Is this why so many of our teachers moved? Damn they had it hard with us, huh?” Baekhyun chuckled.

-

Meanwhile, our poor new teacher drenched in water stood outside the lab with crestfallen look once she noticed how badly damaged the lab was. She let out a horrified shriek when the thought of having to pay back for the damaged came into her mind. She would be in debt for her whole life!

What saddened her even more is the fact that it’s the first day of her teaching XO class and already she became a total mess because of the kids that leave her behind all alone at the lab. Now she was beginning to understand the worries of her fellow teachers. Storming her way to the teacher office, she roughly yanked opened the door and screamed, “I QUIT. I’M MOVING AWAY FROM THIS SCHOOL!” Leaving every teachers and vice principal there gaping at her in shock. The new teacher in a drenched dress, face dirty from all the smokes and blister in the lab with messy hair was quite the sight for them.

-

Minri was seated on one of the bed in the clinic, sitting cross legged and playing with her phone waiting for her target to come. Not one minute later, Xiumin pushed the door opened and he came in with Luhan carrying Chen and putting him on the bed beside where she was sitting.

Xiumin turned to Minri and sighed, “You’re unbelievable.”

Minri pouted, “It’s not that bad. I got burn and fell into coma for 2 days!”

Luhan ruffled her hair, “When will you two stop?”

Minri pursed her lip into thin line, not being able to answer those two people for the reason she and Chen fell apart are only known by them two. Xiumin and Luhan just shook their head at her. Chen groaned signaling that he’s waking up from the short slumber he felt into unconsciously before leaving the lab. Xiumin and Luhan left the room to give space for the two pranksters.

Chen opened his eyes only to be met with a smirking Minri. He scoffed, “You got me bleeding!”

“Pft that’s nothing compared to my injured leg with third degree burn AND falling into coma for 2 days!” Minri retorted.

“You got the lab exploding.”

“You got the lab burning.”

“Is this really necessary?”

“You started it.”

“Excuse me, YOU started it! That night at the pool!” Chen said, a bit outrage.

“I told you it was an ACCIDENT but you went on full prank mode on me the next day so I had to pay you back for that!” Minri shot back.

“Wait, do you hear that?” Chen suddenly asked.

“What?!” Minri snapped, annoyed.

“That, my dearest fiancé, is the sound of your mom grounding you for injuring me, your fiancé!” Chen said, cat like smile gracing his face.

Minri smiled a sweet smile, so sweet it gave Chen a shiver down his spine, “It’s all worth it, dear fiancé. I had you a big scar on the forehead. Gonna take quite the time to heal, no? Besides, your punishment was way heavier than mine.” Then she stood and left Chen in the clinic alone.