Mildly obscene (6)
I believe the answer is:
smutty
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">mildly obscene</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 smutty that I've seen before include "Blue" , "Rather indecent" , "Filthy" , "Rather rude" , "Improper" .)