Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:6/8
K:D
['FAA dAA BAB', 'dcd fff ggg afd efd faf ggg']  
X:1
L:1/8
M:6/8
K:D
|: FAA dAA | BAB dAG | FGA dfe | dBB BAG | FAA dAA | BAB def | g3 fed |1 edB BAG :|2 edB B2 g |: 
 faf g3 | afe dcd | fff ggg | afd efd | faf ggg | afe def | ggg fed |1 edB B2 g :|2 edB BAG ||  