Takeyama Osahiro

 (竹山長宏), also known by his stage name OSA, is a member of LAST FIRST and a former founding member of JOYS.

Profile

 * He has been singing in choirs since he was a child and formed the R&B vocal group JOYS.
 * After a hiatus, he devoted himself to working behind the scenes as a vocal trainer.
 * In 2016, he received an offer from member Yousuke, and decided to go back to the stage and start his career as a member of LAST FIRST.