Good person overcomes hesitation about making porn (4)
I believe the answer is:
smut
'porn' is the definition.
(I've seen this in another clue)
'good person overcomes hesitation about' is the wordplay.
'good person' becomes 'st' (saint).
'overcomes' means one lot of letters goes inside another.
'hesitation' becomes 'um' (sound made when hesitating).
'about' shows that the letters should be reversed in order.
'um' written backwards gives 'mu'.
'st' going around 'mu' is 'SMUT'.
'making' is the link.
(Other definitions for smut that I've seen before include "blue material" , "Soot flake or sexual innuendo" , "Disease of cereal grass" , "Small flake of dirt" , "Sooty matter" .)