Sort of man to join the head of department for a meal (5)

I believe the answer is:

inner

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'sort of man' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for inner that I've seen before include "Not quite bull's-eye" , "Target next to bull" , "Inside; next to the bull (archery)" , "Region around bullseye" , "Essential - most private" .)

I've seen this clue in the Evening Standard.

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