Alas, sad Sid, missing Violet, is full of lust (9)
I believe the answer is:
salacious
'full of lust' is the definition.
(salacious means overly lustful or sexual)
'alas sad sid missing violet' is the wordplay.
'sad' indicates an anagram.
'sid' becomes 'Vicious' (Sid Vicious from the Sex Pistols).
'missing' is a deletion indicator.
'violet' becomes 'vi'.
'vicious' with 'vi' removed is 'cious'.
'alas' with letters rearranged gives 'sala'.
'sala'+'cious'='SALACIOUS'
'is' is the link.
(Other definitions for salacious that I've seen before include "Arousing lustful feelings" , "Arousing lustful thoughts" , "Steamy" , "Prurient, bawdy" , "Lewd" .)