Sensual indulgence rued by each involved (10)
I believe the answer is:
debauchery
'sensual indulgence' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'rued by each involved' is the wordplay.
'involved' is an anagram indicator (involved can mean confusing or complex).
'rued'+'by'+'each'='ruedbyeach'
'ruedbyeach' with letters rearranged gives 'DEBAUCHERY'.
Can you help me to learn more?
(Other definitions for debauchery that I've seen before include "dissolution" , "Indecent behaviour" , "Excessive indulgence in sex, alcohol, or drugs" , "Excessive intemperance" .)