I specifically like “Euphoria” among many BTS songs because it has a voice that’s between a very young boy and a very mature man. And that’s why I had a tough time recording it. I had to translate those emotions into the recording, and I went into it thinking that I have lost my original voice and I really didn’t know how to sing. And I think those emotions I felt translated well into the recording. After listening to the whole thing, I was like, “Wow, I really did a good job.”

—Jung Kook via Rolling Stones

I wanted to write the lyrics of “Euphoria,” but I didn’t take part a lot in the them. I was all over the place during “FAKE LOVE” promotion, and I was too busy to write the lyrics. I kept putting it off. Turns out a lot of people helped finishing the song. I supervised and changed a few words for pronunciation. I wrote the bridge part. And “When I’m with you I’m in utopia”—utopia and euphoria sound similar, so I added that line. As for the line “I hear the far-away ocean,” the original line was “I hear the far-away waves.” There is an animation film called The Ocean Waves. It’s a very romantic animation. I thought the vibe of the animation and the emotions of the song fit together. “I hear the ocean” is something you learn at school. Synaesthetic imagery. So I changed it to “I hear the ocean” and I’m happy with the result. […] Jung Kook worked on the song with great affection. He has re-edited the song so many times. He kept letting me listen to the new version. The first time I heard the guide version of “Euphoria”—the lyrics and Jung Kook’s recording—was almost a year ago. […] When I first heard “Euphoria” I loved the song and beat, and the lyrics were beautiful, but when I first heard Jung Kook’s guide version, he did really great, but it was a bit boring. I wanted him to put more emotion while singing the song. […] That is why Jung Kook recorded this song for revisions five or six times. As a result, as you can hear, it turned out to be a perfect song.

—RM via V Live