Osiris was created as a figurehead for those in power in Egypt who wanted to retain their rapidly dwindling influence. However, she learned what it meant to be a real Pharaoh and this sealed the fates of those who would use her. It is likely that Oswald knew that this would be the likely outcome.
Osiris can be cruel and arrogant but kind and thoughtful when it comes to the people who support her and to those she rules over.