Recluse just recalled sex with ecstasy (7)
I believe the answer is:
eremite
'recluse' is the definition.
(thesaurus)
'just recalled sex with ecstasy' is the wordplay.
'just' becomes 'mere' (I've seen this in other clues**).
'recalled' is a reversal indicator.
'sex' becomes 'it' (a common euphemism).
'with' means one lot of letters go next to another.
'ecstasy' becomes 'e' (informal term for the drug).
'mere' reversed gives 'erem'.
'erem'+'it'+'e'='EREMITE'
(Other definitions for eremite that I've seen before include "Christian hermit or recluse" , "desert father" , "Religious person" , "ascetic" , "Solitary" .)