Sora will take the book back when Riss is done. No comment is made about the fact that she apparently doesn't need to keep it; he's met people with perfect memories before, and he even has a spell that lets him read a book just by touching it.
The contents of the book are as Sora said; well spoken without overly long words as it describes the inns and outs of beginner level magic. There's nothing about the book that would prevent the recording, though there are a few complex diagrams.
"Feel free to stick around and use my place as long as you need. I'm sorry I can't see you out, but at this point, I rather need a nap."