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Phantom's agency WA Entertainment tweeted, "[PHANTOM POWER] D-6 (5/19 release) PHANTOM - Seoul Lonely(feat. Gain of Brown Eyed Girls)", along with the friendly snapshot of Phantom and Ga In looking not so 'lonely' together in the studio.

Ga In shared, "Among the featuring offers that came in, I liked 'Seoul Lonely' the best. My voice suits this song and it felt like it needed it the most so I took part in it... Like the lyrics, 'Today of all days, I feel lonely, especially lonely', I tried to put in emotions as much as possible as if I were lonely, even though I wasn't as I was surrounded by an all male staff at the studio."

Stay tuned for what is sure to be an amazing collaboration as Phantom's first full-length album 'PHANTOM POWER' drops on the 19th!