Actually Sett's dad is Vladimir (just a teory)

Actually Sett's dad is Vladimir. If you look Vladimir story's he's joined a Noxus court for a wild time and she's leave and do a "solo warrior". " In the past, he deigned to join the Noxian noble courts during the most interesting of times, only to fade into seclusion decades later, his extreme age—and the atrocities his sorcery could wreak—a well-kept secret. Even so, under Vladimir’s tutelage, the art of hemomancy has found a place in the military of Noxus, and among scions of the old aristocracy."