Doojoon celebrated his birthday at the fan signing event for B2ST's latest comeback with "Good Luck".

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Fans prepared a surprise birthday party for Doojoon as well as a cake shaped as a soccer ball fitting for the face of of South Korea's professional soccer association league, K-League. The boys have been snagging up the #1 trophies on music shows, so the event was an even better occasion.

Congratulations to B2ST on their latest win on 'Show! Music Core' once again!