Bother group that's devoted (7)
I believe the answer is:
adoring
'devoted' is the definition.
(I've seen this before)
'bother group' is the wordplay.
'bother' becomes 'ado' (both can mean fuss or commotion).
'group' becomes 'ring' (a ring is a criminal organisation).
'ado'+'ring'='ADORING'
'that's' acts as a link.
(Other definitions for adoring that I've seen before include "Giving great love" , "Showing great affection" , "Very keen on" , "Extravagantly indulgent" , "Devoted" .)