Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/8
M:12/8
K:Edor
['G2 G', 'dBA Bcd e2 e efe dBA Bef']  
X:1
L:1/8
M:12/8
K:Edor
|: G2 E FED BEE BEF |1 G2 G AGA Bze dBA ||2 G2 G AFD FED E2 :: F | G2 G AGA Bze dBA | 
 Bcd e2 e efe dBA | Bef gfe dBd AGF | B2 E FED BEE E2 :|  