A left ear — and ear's sexy! (6)
I believe the answer is:
erotic
'sexy' is the definition.
('erotic' can be similar in meaning to 'sexy')
'a left ear and ear's' is the wordplay.
'left' indicates named letters should be taken away.
'and' means one lot of letters go next to another.
'ear' becomes 'otic' (I've seen this before).
'ear' with 'a' taken away is 'er'.
'er'+'otic'='EROTIC'
(Other definitions for erotic that I've seen before include "Amatory" , "Titillating" , "Sexually arousing" , "Sexy" , "Dirty - blue" .)