Flower masking very soft body part (6)
I believe the answer is:
nipple
'body part' is the definition.
(nipple is a kind of body part)
'flower masking very soft' is the wordplay.
'flower' becomes 'nile' (Nile is an example).
'masking' means one lot of letters goes inside another (inserted letters are covered up or masked).
'very soft' becomes 'pp' (musical abbreviation for pianissimo).
'nile' placed around 'pp' is 'NIPPLE'.
(Other definitions for nipple that I've seen before include "Oil supplier" , "Teat" , "Source of mother's milk" , "Chest projection" , "private area" .)