SSSpy isn't a normal spy In his own words he is smarter, handsomer, stronger, agiler and much more.
He is french and edge because he was abandoned by his family and friends.
Like his squad of Demoman, they see them as there worst enemies, because they always kill each other(Like every Merc does) but they are especially trained to kill this specific class.
Anyway he loves no one on the contrary of the others from the squad, as so edgy he is.