Person at home — desire to be outside (5)
I believe the answer is:
being
'person' is the definition.
(I've seen this in other clues)
'home desire to be outside' is the wordplay.
'home' becomes 'in' ('he's home' can mean 'he's in').
'desire' becomes 'beg' (to beg for something is to desire it).
'to be outside' means one lot of letters goes inside another.
'in' put into 'beg' is 'BEING'.
'at' is the link.
(Other definitions for being that I've seen before include "Existence" , "Human, perhaps" , "Living thing" , "Existing" , "A living creature" .)