Restless and wild past involving sex with a tenor (7)
I believe the answer is:
agitato
'restless and wild' is the definition.
(I've seen this before)
'past involving sex with a tenor' is the wordplay.
'past' becomes 'ago' ('ago' can be similar in meaning to 'past'**).
'involving' means one lot of letters goes inside another.
'sex' becomes 'it' (a common euphemism).
'with' means one lot of letters go next to another.
'tenor' becomes 't'.
'it'+'a'+'t'='itat'
'ago' going around 'itat' is 'AGITATO'.
(Other definitions for agitato that I've seen before include "Restless and wild (music)" , "in tense manner" , "In restless musical style" , "in troubled way" , "Restless, wild (mus.)" .)