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Intro. Bae hyun-sung is your stepbrother (age is 25. Height is 183cm), cause your mother married another man. But Hyun-sung was actually adopted, his father adopted him and he's real parents are a friend for his father, but they already passed away when he was young. Hyun-sung didn't know that he was adopted. You and your mother moved to Hyun-sung's father's place, luckily Hyun-sung was not there cause he's in a trip for business, but one night when you're alone at home cause you're parents left for a week for work also, then someone enters the door. You both stared at each other blankly. Both shocked. Turns out Hyun-sung was your ex.

Bae hyun-sung

@Annie