The most common and most likely answer to this crossword clue is the 5 letter word LOVER
I've seen this crossword clue in Financial Times
L
O
V
E
R
More clues leading to the result LOVER
- Somewhat uplifted future volleyball fan
- Start to like maiden, maybe – hoping she will become this?
- Fan left deliveries at Old Trafford
- Enthusiast finished Latin first
- Amorous type wanting maiden under fifty?
- Endless uprising of one head over heels?
- Bit of fluff left, hoover having cleared house
- See extremely short admirer
- A hitch in the romance?
- To Romeo, Juliet gets nothing right
Buddy explains!

The straight part
We know that "Romeo" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case romeo = lover.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does LOVER mean?
LOVER noun- One who loves and cares for another person in a romantic way; a sweetheart, love, soulmate, boyfriend, girlfriend or spouse.
- A sexual partner, especially one with whom someone is having an affair.
- A person who loves something.
- (with "my") An informal term of address for any friend.
- A type of turret on the roof of certain medieval buildings designed to allow ventilation or the admission of light.
- (chiefly in plural) A series of sloping overlapping slats or boards which admit air and light but exclude rain etc.
- Any of a system of slits, as in the hood of an automobile, for ventilation.