Breaking up fun, he’ll become awkward (9)
I believe the answer is:
unhelpful
'awkward' is the definition.
Both the answer and definition are adjectives. Perhaps they are linked in a way I don't understand?
'breaking up fun he'll' is the wordplay.
'breaking' indicates an anagram.
'up'+'fun'+'hell'='upfunhell'
'upfunhell' anagrammed gives 'UNHELPFUL'.
'become' is the link.
Can you help me to learn more?
(Other definitions for unhelpful that I've seen before include "disobliging" , "Not co-operative or of assistance" , "One doesn't expect a daily to be so" , "Not of assistance, probably the opposite" , "Uncooperative, useless" .)