Former president, human being without least bit of sense (5)
I believe the answer is:
peron
'former president' is the definition.
(Juan Peron, Argentine president)
'human being without least bit of sense' is the wordplay.
I cannot really see how this works, but
'bit' could be 'o' (resembles 0, a binary digit or bit) and 'o' is located in the answer.
'human' could be 'rn' (RN is an example) and 'rn' is present in the leftover letters.
This explanation may well be incorrect...
(Other definitions for peron that I've seen before include "Argentinian president, Evita his wife" , "Prone to being an Argentine president" , "Former Argentine leader" , "Juan, maybe" , "Surname of Evita of the musical" .)