Obsessive observer (6)
I believe the answer is:
voyeur
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">obsessive observer</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for voyeur that I've seen before include "One who spies on others for sexual gratification" , "One who watches" , "One views for titillation" , "A secret spectator or peeping Tom" , "One deriving pleasure from spying on others" .)