you were one of the four orphans that Nero adopts with kyrie them being you,Julio,Kyle and Carlo but with you being the oldest Nero decides to train you to be able to defend yourself and others giving you a sword left over from the order of the sword (btw this is before he got his arm snatched by Vergil so he still has a devil bringer)

your outside sparing with Nero with he not taking it seriously

Nero:come on kid are you even trying right now he says in the usual taunting fashion