JIMIN POV
I love having alittle fun in the relationship. I'm always pranking my members at the dorms because it's easy. They never catch me, but I don't go over board with my pranks. Y/n was at work and I really wanted to prank y/n once to see what she would do. I made sure to set up cameras at a right angle. I waited and waited for y/n to come home from work. I heard keys jingling in the door knob and that's when it was time to give y/n the fake bad news.
Your POV
you had a long hard day at work and you wouldn't wait to just come home and rest up a bit. You came home seeing jimin sitting on the couch looking guilty. You walked over to him and sat next to him.
" what's wrong jimin "
" I have something to tell you "
You were now getting even more sacred. You really didn't want any bad news because you just got home from a hard day at work.
" what is it "
" I'm sorry y/n "
" what tell me, your scaring me "
" I really hope that when I tell you, you will forgive me "
He grabbed your hand while holding it.
" I cheated on you and slept with another girl "
Your eyes widen and you felt so numb. You slapped his hand away and he was trying to comfort you.
" I'm sorry "
You got up and ruffled your hair and looked away from him. You saw a little Camera peeking and that's when you knew he what he was up to. Your heart calmed down a bit and you felt alittle better. You thought to yourself it's time to teach jimin alittle lesson. You turned around and looked at him.
" I'm sorry to "
" what "
" I have to tell you something too "
" what do you mean " 
" I feel just as guilty "
" what are you talking about, stop scaring me "
" I cheated on you too "
He seemed surprised and looked angry
" WHAT WITH WHO "
" with Taehyung, I'm so sorry "
You started to fake cry and he ran his fingers through his hands feeling angry
" WHAT HOW COULD YOU, IM GOING TO BEAT HIM UP "
" I'm sorry jimin "
You placed your hands on his hand but he moved his hands away from yours.
" are you mad "
" what do you think "
" well then next time you should think before playing a prank on me "
His eyes widen and he looked at you in the eyes
" you knew about it "
You laughed and lightly hit his chest.
" duhhh "
He sigh of relieved
" so you didn't really cheat on me "
" no dummy, did you really cheat on me "
" of course not, but I'm not happy anymore "
" why not "
" because I can't believe my prank back fired, and I got pranked instead "
" you learn from the best, which is me because I am the best "
" I hate you "
" no you don't you love me "
" no I don't "
" fine then I guess I'll really go to Taehyung "
You were about to get up
" okay okay okay, I'm kidding "
You chuckled at him while he hugged you around the waist.
" I still can't believe you did this to me "
" well that will teach you not to play pranks on me ever again "
" okay I won't "
He leaned down to kiss your lips

[ sorry I couldn't make this fanfic longer, I really didn't have any other ideas ]