Endless drama producing tension, avoiding sex (8)
I believe the answer is:
platonic
'avoiding sex' is the definition.
(as in a platonic relationship)
'endless drama producing tension' is the wordplay.
'endless' means to remove the last letter.
'drama' becomes 'play' (synonyms).
'producing tension' becomes 'tonic' (tonic can mean producing tension in muscles).
'play' with its final letter taken off is 'pla'.
'pla'+'tonic'='PLATONIC'
(Other definitions for platonic that I've seen before include "Purely spiritual (love)" , "sort of solid" , "Some friendships are" , "Latin cop in kind of non-sexual romance" , "I can plot (anag)" .)