Depraved emperor (4)
I believe the answer is:
nero
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">depraved emperor</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 nero that I've seen before include "Roman Emperor notorious for vice and luxury" , "Imperial Roman fiddler" , "Ancient Roman emperor" , "Roman emperor on the fiddle?" , "Roman arsonist and fiddler" .)