Rid oneself of sin? This woman won’t (3-5)

I believe the answer is:

she-devil

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'rid oneself of sin? this' is the definition.
The definition suggests a singular noun which matches the answer.

'woman won't' is the wordplay.
'woman' becomes 'she'.
'won't' becomes 'devil' (I can't explain this - if you can you should believe this answer much more).
'she'+'devil'='SHE-DEVIL'

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(Other definitions for she-devil that I've seen before include "woman like Lilith" , "Malicious and spiteful woman" .)

I've seen this clue in The Times.

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