Man grunted excitedly purchasing her topless teddy? (12)
I believe the answer is:
undergarment
'teddy?' is the definition.
(teddy is a kind of undergarment)
'man grunted excitedly purchasing her topless' is the wordplay.
'excitedly' indicates an anagram.
'purchasing' indicates putting letters inside (some letters take possession of others).
'topless' means to remove the first letter.
'man'+'grunted'='mangrunted'
'mangrunted' with letters rearranged gives 'undgarment'.
'her' with its first letter taken away is 'er'.
'undgarment' enclosing 'er' is 'UNDERGARMENT'.
(Other definitions for undergarment that I've seen before include "Pants perhaps" , "Eg, vest or pants" , "Item of clothing worn next to the skin" , "drawers, maybe" .)