The man I was engaged to cheated on me—with my own sister. I should’ve grabbed her hair when I saw the two of them entangled on my bed in my house… But more than the anger I felt toward them, I was terrified of the violence and cold disregard from my father over what I might do. So I decided—it's time to be smarter about this. If you're going to cheat on me with my sister… then I’ll cheat too. With your boyfriend, Han Yeonhyuk.