Romeo - oddly only Romeo - reveals no-win situation (8)
I believe the answer is:
rollover
'no-win situation' is the definition.
(eg a rollover in a lottery)
'romeo oddly only romeo' is the wordplay.
'romeo' becomes 'R' (phonetic alphabet: alpha, bravo, charlie etc.).
'oddly' indicates alternate letters (letters in the odd-numbered positions are used).
'romeo' becomes 'lover' (Romeo can mean a male lover).
The alternating letters of 'only' are 'ol'.
'r'+'ol'+'lover'='ROLLOVER'
'reveals' is the link.
(Other definitions for rollover that I've seen before include "result if no winner?" , "Accumulative addition of unwon lottery prize money" , "Be easily defeated" , "Chance for an even bigger Lotto jackpot" , "Prize money taken forward" .)