Lechery by Romeo -- and, ultimately, Charlie Sheen (6)
I believe the answer is:
lustre
'sheen' is the definition.
(I know that sheen can be written as lustre)
'lechery by romeo and ultimately charlie' is the wordplay.
'lechery' becomes 'lust' (I've seen this in other clues).
'by' is a charade indicator (letters next to each other).
'romeo' becomes 'R' (phonetic alphabet: alpha, bravo, charlie etc.).
'and' means one lot of letters go next to another.
'ultimately' suggests the final letters.
The last letter of 'charlie' is 'e'.
'lust'+'r'+'e'='LUSTRE'
(Other definitions for lustre that I've seen before include "Sheen or renown" , "Gloss, brightness" , "Rustle with shine on surface" , "Glory, distinction" , "Gentle sheen/glow" .)