French composer with obligation to follow it (5)
I believe the answer is:
satie
'french composer' is the definition.
(French composer Erik Satie, 1866-1925)
'obligation to follow it' is the wordplay.
'obligation' becomes 'tie' (I've seen this before).
'to follow' is a charade indicator (letters next to each other) (some letters go after or follow others).
'it' becomes 'sa' (old-fashioned abbreviation for sex appeal).
'tie' put after 'sa' is 'SATIE'.
'with' acts as a link.
(Other definitions for satie that I've seen before include "Erik -, nineteenth to twentieth century French composer" , "scorer" , "posed by yours truly close to stage" , "French avant-garde composer, Erik, d. 1925" , "creative Frenchman" .)