Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
M:6/8
K:Gmin
['BAG FDC', 'G2 D GBd g^fg dec BAG Fac']  
X:1
L:1/8
M:6/8
K:Gmin
 c | BAG FDC | DE^F G2 c | dfd cdc | BAG FGA | BAG FDC | FDE FGA | c/d/fd cAF | AGG G2 :: D | 
 GBd g^fg | dec BAG | Fac f=ef | cdB AGF | GBd g2 a | bag fga | d=ef gd[Ac] | BGG G2 :|  