The most common and most likely answer to this crossword clue is the 4 letter word EMOS
I've seen this crossword clue in Independent
E
M
O
S
Buddy explains!
The straight part
We know that "brooding music fans (i.e. fans of brooding music, although the fans themselves might be brooding as well…)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case brooding music fans (i.e. fans of brooding music, although the fans themselves might be brooding as well…) = emos.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 EMOS mean?
EMOS noun- (early 1990s) A particular style of hardcore punk rock
- (early 1990s) An individual or group of people associated with that subculture and musical style.
- (late 1990s-current) Any form of guitar-driven alternative rock that is particularly or notably emotional
- (late 1990s-current) An individual or group of people associated with a fashion or stereotype of that style of rock.
- (2000s) A young person who is considered to be over-emotional or stereotypically emo.