The most common and most likely answer to this crossword clue is the 6 letter word CHICKS
I've seen this crossword clue in Independent
C
H
I
C
K
S
Buddy explains!

The straight part
We know that "girls" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case girls = chicks.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 CHICKS mean?
CHICKS noun- A young bird.
- A young chicken.
- (term of endearment) A young child.
- A young, especially attractive, woman or teenage girl.
- To sprout, as seed does in the ground; to vegetate.
- A screen or blind made of finely slit bamboo and twine, hung in doorways or windows.