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On the episode, the two idols headed over to Sungjae's agency Cube Entertainment, where he recorded a very special track by fellow BTOB member Hyunsik. While Joy got to talk to the BTOB members, Sungjae suddenly left the room, returning with princess headphones just for Joy.

Sungjae said, "I prepared a song for you. You must be happy." Joy then put on her new headphones and listened to him serenade her with Han Dong Joon's "I Love You". 

In his solo interview, Sungjae commented, "I was thinking about what I should sing to send her my message. I really wanted to sing this song when I found someone I liked." Joy also shared, "I teared up. Oppa's not very good at expressing himself. I really liked that I could feel how sincere he was."

What did you think of Sungjae's song for Joy?