Toheart's Key and Woohyun appeared on SBS's radio program 'Cultwo Show' on March 18 and talked about their close friendship.  

Key first talked about how they got to work together as a new duo group, "When I was close with Woohyun, I told him we should take pictures together, saying, 'It's a simple photo shoot.'  However, people liked it and said, 'Might as well release an album together,' so we got more opportunities."

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Woohyun said, "It's been three years since I became friends with Key.  Whenever I was hungry during my debut days, Key helped me out a lot.  He's a good friend."

The DJs talked about the two being in different agencies, but Toheart elaborated, "Our companies merged.  Our production costs are cut in half and our respective managers follow us around separately."