every group and every idol has or are a composer. on Allkpop that came up with a list of the top 7 idols that has the most copyright songs.
GDragon came in number 1 with the most songs. 160 copyrighted songs! that's amazing! Beast Junhyung came in 2nd with 104 songs along with Zico coming in 3rd with 85. here is the link if you want to read more about it. http://www.allkpop.com/article/2016/03/korea-music-copyright-association-reveals-top-7-male-idol-artists-with-most-copyrighted-songs