I see it as, Your the one crying like a fucking bitch.
"Wahh Wahh Yamato did something I dont like, WAH WAH WAH!"
Your bias against her has blinded you towards the plotlines that she has rn.
The fuck does it even matter if she has his book, She found it and has read it, there's some info that 'could' be useable that's already something. Stealing his persona? Who FUCKING CARES, your so hung up bout it, Do you not understand why she's doing in the first place or are your just going to ignore it?
It's painfully obvious your opinion on the matter is full of shit, and holes.