The most common and most likely answer to this crossword clue is the 5 letter word MIENS
M
I
E
N
S
More clues leading to the result MIENS
Buddy explains!

The straight part
We know that "Looks" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case looks = miens.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 MIENS mean?
MIENS noun- Demeanor; facial expression or attitude, especially one which is intended by its bearer.
- A specific facial expression.