After a good time, extremely sweaty and flatulent (5)
I believe the answer is:
gassy
'flatulent' is the definition.
(I know that flatulent can be written as gassy)
'after a good time extremely sweaty' is the wordplay.
'after' means one lot of letters go next to another.
'a good time' becomes 'gas' (I've seen this in another clue).
'extremely' says to hollow out the word (remove centre letters) (only the extremes of the word are used).
'sweaty' with its middle taken out is 'sy'.
'gas' next to 'sy' is 'GASSY'.
'and' is the link.
(Other definitions for gassy that I've seen before include "Fizzy" , "Verbose" , "Carbonated" .)