Develop a musical composition using the outlined alphabetical depiction of the structure and the provided theme.
X:1
L:1/8
M:9/8
K:D
['gfe fBB', 'd2 e faf']  
X:1
L:1/8
M:9/8
K:D
|: gfe fBB fBB | gfe fBB fga | gfe fBB fga | agf efd cde :: d2 e faf ecA | d2 e faf gec | 
 d2 e faf efg |1 agf efd cde :|2 agf efd cBA ||  