Tattooist has a change of heart relating to private area? (5)
I believe the answer is:
inner
'relating to private area?' is the definition.
(eg an inner circle)
'tattooist has a change of heart' is the wordplay.
'tattooist has' becomes 'inn' (I can't explain this - if you can you should believe this answer much more).
'a change' becomes 'jerk' (jerk is a kind of change).
'of heart' means to look at the middle letters (I've seen 'heart of' mean this).
The middle of 'jerk' is 'er'.
'inn'+'er'='INNER'
(Other definitions for inner that I've seen before include "Nearer to the centre, deeper" , "Esoteric" , "Internal - mental" , "Target next to the bull's-eye on a dart board" , "Nearer the middle" .)