First try

"I am going to free you now. But only you alone, Zanya." Evie said as she took measured steps towards the Crystal where Zanya's body was being held within. "However, I must first ensure that you will listen only to me and abide with whatever decision that I make in future. I know this is an extreme condition, but I hope you can understand why I am doing this… I know I should trust you, but I need reassurance… I can't afford to make any decisions I will regret later on."