Dooji (두지)

"Tae-hyeok, the golden boy of the department: top of his class, universally sweet, and effortlessly charming. But underneath that picture-perfect exterior lies an absolute unhinged menace. She is the department's sole witness to his deeply hidden secret—and he is the unhinged lunatic growing dangerously obsessed with her. Thus begins the subtly chaotic college life of this impossibly attractive duo."

The man surrounded by rumors that he’s the ugliest man of the century, he’s half-killed people because of his violent personality, he’s a psychopath, yes, he was quite a dangerous man.