Zico appeared on KBS 2TV's 'Happy Together 3' on March 24, and revealed a time he was upset with Park Myung Soo in the past.

He said, "I met Park Myung Soo after debut about three years ago.  After that, I became a bit more successful, so when we met again, he asked me for my contact info. But in the past, he hadn't asked for my contact info," causing laughter.

SEE ALSO: 'Running Man' cast shocked by the state of Kim Jong Kook's overwhelmingly messy home as they help clean up

He went on, "So I gave him my mailing address and two songs came.  As expected, they were EDM.  The songs had jungle feels."  Park Myung So asked, "How were they?" and he replied, "Honestly, I'm not good at those types of feedback," causing more amusement. 

The MCs then asked him, "Park Myung Soo says you two are close, but is that real?" and Zico laughed before saying, "I'm closest to Jung Jun Ha from 'Infinity Challenge,' and Park Myung Soo is the one who mentions me well.  He mentions me amongst other big names like IU and G-Dragon," and relayed his gratitude at becoming another 'younger sibling' to Park Myung Soo.

Park Myung Soo then bragged, "EXO's Chanyeol asked me to go to their concert.  Just the other day, IU called me."