The most common and most likely answer to this crossword clue is the 9 letter word EGRESSING
E
G
R
E
S
S
I
N
G
Buddy explains!

The straight part
We know that "coming out" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case coming out = egressing.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.
Crossword Answer definitions
EGRESSING verb- To exit or leave; to go or come out.