The most common and most likely answer to this crossword clue is the 6 letter word JOHNNY
J
O
H
N
N
Y
Buddy explains!

The straight part
We know that "this guy?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case this guy? = johnny.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 JOHNNY mean?
JOHNNY noun- A prostitute's client.
- A device or place to urinate and defecate: now usually a toilet or lavatory, but also a chamber pot or outhouse.
- A Western man traveling in East Asia.
- A male mule.
- A condom.
- An inexperienced new worker, usually an immigrant.
- A hospital gown: a gown with a back opening closed with snaps or ties, worn by hospital patients.