@TheHangedMan Arcadius pasued for a moment, eyes locked on her face, reading her to see if he could find any hidden intentions on what she planned on doing. He'd never really had any help, nor asked anyone, not been asked by anyone that simply tried to make off with the book during the night only to wind up a fragment of their former selves..
In theory he could probably benefit from some help in deciphering the massive book, of course she would benefit as equally in the long run and gain knowledge of spells that could devastate entire cities...but of course with him knowing more than her about the book she'd never be able to realize the full potential of the book without years of study..
After several minutes he spoke "I've given it some thought...and in the years I've had the book its only been myself studying it and dechipering it..perhaps it is time I did get some help studying it."
He paused again, thinking how to phrase the rest of what he was saying. "In the past a few have asked to help me and ended up trying to steal the book during the night. It...didn't turn out well for them..at all. Therefore I will not be making the same mistake again. Until I am able to trust you enough, you will only have access to the book when I am available to make sure you don't steal it, its not you yourself that I don't trust so much as the past history of working with people. Secondly, if you are able to learn something from it, you will only practice it when I am available to witness you do so. If you can agree to those terms, I'll gladly accept your help."
He finished with a smile, perhaps she'd be one of the first real friends in years that wouldn't try to stab him in the back as soon as they had a chance.