Viewer who's turned on first of programmes with cat that's whizzing around (7,3)

I believe the answer is:

peeping tom

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'viewer who's turned on' is the definition.
(person aroused or 'turned on' by watching others)

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for peeping tom that I've seen before include "One who spies pruriently on others" , "who likes looking at females" , "Spy" , "Voyeur" .)

I've seen this clue in The Guardian.

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