Sungjae told the media outlet, "Honestly, the acting for this particular project is really difficult. In my last project, 'School 2015,' my role was a high school student. Because it hasn't been long since my graduation, I got a good sense of how I should talk. But when I saw the synopsis for this drama, I was greatly worried. I'm getting a lot of help and learning a lot from my sunbaes." 

Regarding his decision to take on a project that is totally different from his last, Sungjae said, "I decided to join after seeing the character named Woo Jae. Though the story is dark, he shows off an adorable and bright side on his own. And I like it that he's a character who can investigate with the viewers." 

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The idol-turned-actor continued, "This time the other members have to go on music shows without me. But I asked for permission from my agency because I wanted to focus more on the drama. As a rookie actor that is just beginning [my career], I want to slowly show my acting to the audience."