As a companion with wit, she has charm (5)
I believe the answer is:
witch
'charm' is the definition.
(I know that charm can be written as witch)
'as a companion with wit she' is the wordplay.
I cannot really understand how this works, but
'companion' could be 'ch' (Companion of Honour) and 'ch' is found in the answer.
'with' could be 'w' (abbreviation) and 'w' is located in the answer.
The remaining letters 'it' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'has' acts as a link.
Can you help me to learn more?
(Other definitions for witch that I've seen before include "Female member of coven" , "strange woman" , "'The Lion, the - - and the Wardrobe'" , "charming female" , "Cauldron-stirring hag" .)