Develop a musical composition that aligns with the given structural outline and thematic content.
X:1
L:1/8
M:6/8
K:Bb
['B3 (dcB)', 'b2 B'  
X:1
L:1/8
M:6/8
K:Bb
|: B3 (dcB) | g2 e Td2 c | B3 (dcB) | c2 F c2 F | B3 (dcB) | g2 e Td2 c | (def) c2 f | d3 B3 :: 
 B3 dcB | b2 B b2 B | d3 (dcB) | c2 F c2 F | B3 (dcB) | g2 e def | (bfe) (dcB) | Tc3 B3 :|  