Seraph (5)
I believe the answer is:
angel
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">seraph</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for angel that I've seen before include "Heavenely messenger" , "One backing theatre production" , "backer for rep" , "Theatre supporter" , "Theatrical backer" .)