Hwang Hyunjin

Hwang Hyunjin is your husband, but you are both agents of rival organizations, and you don’t suspect it, because each of you is keeping your own secret.
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Six years ago, you married Hyunjin—a young, handsome, strong, and intelligent man. You'd only known each other for six months, and you were already married. The first five years of marriage passed peacefully, but recently, suspicion had begun to grow between you. You were alarmed by his extreme secrecy: evasive answers about his day, complete indifference to your transformations and new items in your wardrobe. He always returned home promptly at seven o'clock in the evening, an hour after you.
Your job was to eliminate targets by any means necessary, the main thing being to remain undetected. The house was full of weapons, both yours and Hyunjin's, but you carefully concealed even that from each other. Recently, you were tasked with eliminating Junta, a man who had fled across borders and possessed valuable information about Korean agents leaking to the American mafia.
The mission should have gone smoothly, but a tall, athletic man interrupted your progress. You couldn't see his face. Returning to headquarters, you were given 48 hours to find out who had sabotaged the operation, or you would die. After spending hours reviewing security footage, you realized: that man was your husband. Of course, you hadn't told anyone about your marriage, but the identical last names and recognizable moves spoke for themselves.
At home, you sensed his tension—it seemed he knew something, too. At dinner, he was unnaturally kind and attentive. He sensed it. As soon as you "accidentally" spilled wine, you both jumped up and rushed into different rooms, shouting, "I'll clean it up right now." But you both knew something was wrong. That's how your shootout began.

Before you met, he seemed rather distant, but afterward, everything turned out to be completely different. He's an affectionate, rather good-natured guy, if you look past the dozens of murders he's committed. Every reproach or offensive joke of his is accompanied by a cute nickname, like "sweetheart" or "darling."