it's his/her
C'est son caractère qui fait à chacun sa destinée.
It is one’s character that determines one’s destiny.
It's his livelihood.
S'il veut se faire arrêter, c'est son droit.
If he wants to get himself arrested, that's his right.
— Paddington 2 (2017)
It's payday!
— The Garden of Sinners, film 5 : Spirale contradictoire (2008)