Ginger cat is a character Alice encounters (3,5)

I believe the answer is:

red queen

'a character alice encounters' is the definition.
(character encountered by Lewis Carroll's Alice)

'ginger cat' is the wordplay.
'ginger' becomes 'red ginger' (red hair).
'cat' becomes 'queen' (a queen is a female cat).
'red'+'queen'='RED QUEEN'

'is' is the link.

(Another definition for red queen that I've seen is " one seen through the glass?".)

I've seen this clue in The Independent.

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