Crossword Genius

Fan like this in part of the UK visiting the Orient (10)

Ross

I believe the answer is:

enthusiast

But I can't explain it at all!

(Other definitions for enthusiast that I've seen before include "Devotee" , "Fan" , "buff" , "One deeply interested in a subject" , "one not at all cool" .)

I've seen this clue in The Times.
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