Very funny sex with a Dolores (6)
I believe the answer is:
lolita
'dolores' is the definition.
(Lolita is a nickname for Dolores)
'very funny sex with a' is the wordplay.
'very funny' becomes 'lol' (internet acronym for laugh out loud).
'sex' becomes 'it' (a common euphemism).
'with' is a charade indicator (letters next to each other).
'lol'+'it'+'a'='LOLITA'
(Other definitions for lolita that I've seen before include "1958 novel by Vladimir Nabokov" , "Literary nymphet" , "Nabokov novel about a nymphet" , "Seductive young girl" , "novel title" .)