Classes start and you follow the schedule. Your teachers and instructors are kind, but the classes are extremely hard. After every class, you have to practice for a whole hour afterwards. You're exhausted by the time it's noon, and you don't even have appetite to eat anymore. Finally, classes are over and it's time to practice until you basically can't do it anymore. It's about 8pm and you begin to practice the choreography you just learned a couple hours ago. 
You hear a loud knock on the door. Though the door has a large window on it, you rolled down a small curtain before you started practicing, just to make sure that no one sees you. 
Aish! Who is that?! you think to yourself. 
You walk towards the door and open it. You see Mark outside the room giving you a death stare. 
"Who are you? I need to practice. Move," he snaps, pushing you away and not even recognizing you. 
"Couldn't you see that I closed the curtain for a reason! I'm practicing!" you yell, watching him walk towards the middle of the room. 
"I always use this room. If you want to practice, then you can go somewhere else," he tells you, not even looking at you. 
"Yah! Get out! Who do you think you are? Just because you're my sunbae doesn't mean that you have to be so rude and arrogant!" you tell him, stomping your foot and getting furious. 
"Doesn't that answer your question? I am your sunbae and that makes me superior. Also, you spilling your iced coffee on my Gucci jacket didn't help me to be nicer to you either. So, please leave. It's a request," Mark casually tells you, giving you a small, evil grin. 
You're so speechless and your anger starts to build up a lot inside of you. You want to scream and yell at him even more, but you don't want to get in trouble on your first day. So, you just take your bag and quickly run out the door. You hear Mark snicker from inside the room as you exit. 

//The next morning//

You're in your vocal class and you can barely focus. Your teacher has asked you to do a couple of warm-ups and you can't stop thinking about Mark. 
"Y/N, it's only your second day and you sound like you've been here for more than five years. What's wrong?" your teacher asks you. She shuts the piano and looks at you in the eyes to listen to you. 
"Uh...well," you start, not really wanting to go on. 
"Please tell me. I don't want you to have a hard time during classes," she tells you, giving you a smile. 
"Mark...uh...Mark," you stutter, looking down. 
"Ah, Mark. Our precious, sweet baby boy of the company who is now an arrogant, grown-up man," she sighs. 
"It seems like everybody knows the story," you quietly say. 
"Yes, everybody does know. We've tried to get other trainees to change him, but he still hasn't changed," she tells you. 
"That's it! I'm going to change him!" you tell her, getting rid of your shyness. 
"It won't work. We've been trying it for months and it still hasn't worked," your teacher says. 
"No. It will work. No matter how rude or arrogant he is, I'm going to make sure he changes, because I will not deal with fangirls loving a guy that they don't know is really arrogant and rude when he's not on stage. I'm going to bring the old Mark back," you enthusiastically say, sounding so determined. 
"What?! No! You don't have to! Trust me, it won't work," she tells you. 
"Ugh fine," you say as you give up. 
You continue with your lessons throughout the day. It's the same schedule and classes, and they're all so tiring. Your whole day is basically just learning and practicing, and that's it. You find an empty practice room at the end of the day and you make sure that it's vacant. While practicing, you hear a knock on the door. 
Uh oh. Is it Mark again? you think, getting nervous. You walk towards the door and slowly open it, trying not to be so nervous. You see Koeun and you let out a sigh of relief. 
"Ah! Koeun-ah! Come in!" you tell her, getting excited. 
"No, it's okay! I know you're practicing! I was just handing out flyers to all of the trainees," she smiles, handing you a white piece of paper. 
"What is this?!" you exclaim, looking at the paper. The flyer says that beginning tomorrow, all of the new trainees will receive personal training from an NCT member for the next two months. 
"It's an official announcement from the president that you and I think about 17 more of the new trainees will be receiving personal training from one of your sunbaes!" she excitedly says, "Oh! And here's the assignment chart." 
You quickly grab the paper and see that all of the new trainees are assigned to one NCT members. You quickly look for your name and your heart stops. 

Kim Y/N - Mark Lee

"Oh my gosh! No way!" you exclaim, getting furious. 
"Why?! Who did you get?! Did you get Mark?!" she asks, stealing the paper away from you. 
You nod and she opens in shock. 
"Omo! This must be fate!" she laughs, giving you the paper back. 
"Ugh! Why?! Why is this happening to me?!" you groan.
"Isn't this a good thing though? Didn't you want to change him?" Koeun winks. 
"Mwo?! Who told you that?!" you worriedly ask. 
"Y/N, we have the same vocal instructor. She told me, because we're roommates," Koeun replies with a sweet smile. 
"Ugh! I'm going crazy!" you yell, sitting down on the ground. 
Koeun laughs, "It's going to be okay, Y/N! I gotta go now and pass out the rest of these. Bye!" 
She sweetly smiles and skips out the door, feeling happy for no reason. 
You continue to practice, trying to get the idea of Mark being your instructor out of your mind. 

//8:45am the next morning//

Your knees begin to shake as you walk towards the company from your dorm. You heard that the NCT members do not know who they are teaching, and the idea of that makes you even more nervous. 
What will Mark do when he sees that I'm his student?! you think, opening the door to the vocal room. You see Mark sitting down, wearing a Mickey Mouse hat backwards. He is wearing a baggy black and white Crooks and Castles sweatshirt and jeans. He taps his feet inside a pair of black Vans and he hums the music that you are about to sing. 
"Uh...Mark," you quietly say, gently tapping his shoulder. 
He turns around and his eyes widen, "