Snake present, writhing around (7)
I believe the answer is:
serpent
'snake' is the definition.
(I know that snake can be written as serpent)
'present writhing around' is the wordplay.
'writhing around' is an anagram indicator.
'present' is an anagram of 'SERPENT'.
(Other definitions for serpent that I've seen before include "Tempting" , "Present (anag.)" , "the first lady found beguiling" , "Limbless reptile" , "Present for a snake" .)