Joon-Sun

A person who is really smart, presidential, and great at spamming others.

John: Joe kept spamming gmail chat last night!
Bob: Wow, he is such a Joon-Sun

by KimJongUn May 16, 2012

Sung-Joon

"Sung-Joon" is a slang term for someone who purposefully irritates others whilst acting oblivious to his/her actions.

Person X posts a photoshopped picture of Y to irritate him/her

Y: "why did you do that?!"
X: "ha...what are you talking about?"
Y:"You know what I mean!...your such a Sung-Joon"

Another example:

Person X falsely claims to have beaten up person Y in a sad attempt to gain clout from his/her peers.

Y: "Why are you telling people that you beat me up?"
X: (Giggling)"because I did"
Y: "What are you on about? Your such an SJ!"

by O-Poggers August 8, 2020

Joonsung

The best human being in the world and so good. Everyone loves him

Joonsung is good

by Kristofer Oreo bkarnison July 5, 2021

Joonsung

The hottest guy on the planet. Typically seen brooding and staring out of windows, the Joonsung is quite handsome. The Joonsung is also typically a dumbass.

"Why are you chewing on your pencil? You're being such a Joonsung."

by DAN THE FOOT MAN October 7, 2021