The most common and most likely answer to this crossword clue is the 3 plus 6 letter word CON ARTIST
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More clues leading to the result CON ARTIST
- Critic on art is trendy hoaxer at heart
- Constable possibly tailing Tory fraudster?
- Position managed backwards in bed for Hustler
- Swindler in bed, suffering strain
- One who does awkward strain in bed?
- Criminal transaction excludes one fraudster
- Fraud busted, cast into Tihar at last
- Crook — his heart in contrast is crooked
- Trickster on breaking vehicle first …
Buddy explains!

The straight part
We know that "One who does" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one who does = con artist.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.