Comparatively dissolute sort off the grub (6)

I believe the answer is:
faster
'comparatively' is the definition.
Both the answer and definition are adverbs. Perhaps they are linked in a way I don't understand?
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for faster that I've seen before include "More speedy" , "Speedier" , "One refuses to eat" , "Person going hungry" , "A person who refuses to eat" .)
