Premise: Lee Jae-jin (Hangul: 이재진 ; Hanja: 李在真 ; Japanese:イ•ジェジン born December 17, 1991) is a South Korean musician and actor. He is a member of rock band F.T. Island, where he serves as the bassist and 2nd vocalist. He has also contributed to F.T. Island's body of work with several compositions of his own.
Hypothesis: Lee Jae- jin has never written his own music.