members -- vocals ( 2003 -- present ) -- bass , backing vocals ( 2003 -- present ) -- drums ( 2003 -- present ) -- guitar , backing vocals ( 2007 -- present ) -- keyboards , synthesizer ( 2007 -- present ) ; former members -- guitars , backing vocals ( 2003 -- 2007 ) equipment yu-ki ( keyboards ) uses a korg x50 and a yamaha mo6 in a firm ultimate ax48b rack .