scarlet university is one of the most prestigious schools at the country but despite of being one of the most prestigious schools, scarlet university hides a lot of secrets; secrets which were never revealed. eva, a simple, bubbly and positive girl who only wants to survive, graduate and have a stable job was accidentally accepted as a scholar at scarlet university. 

"before 10pm strikes, you have to be inside your room, or else you are dead."
"have you ever heard about nct?"
"what nct?"
"you have to avoid them."
"but why?"
"they are dangerous."

nct. a group of 18 guys which are sons of underground mafia and gang bosses around korea and china who were also the board of directors of scarlet university which no one knows. the only thing the students and teachers know about them is that they are a bunch of guys which only know how to fight and draw blood around the campus. 

upon eva's stay at scarlet university, she meets all 18 members at different events unknowingly. and unconsciously, she breaks the wall built by these 18 boys towards making friends and finding love as these boys repeatedly save eva from trouble and from all those who bullies her. and by knowing these 18 boys, eva discovers a lot about her real personality and real family that would hinder her relationship with these guys.

will they fight for what they truly feel? or will they just give up the friendship that they found?