He was able to do so by using Ui Ui's technique ... However, even before the flames can touch Yuji, Choso creates a Blood Barrier to save him. Tragically, he ended up sacrificing himself.

In Choso's very own words, Yuji had now become a Demon God ... and perhaps his awakening would help him do that as well. If that is the case, then Yuji will become the first sorcerer in history ...