'Book' was a metonymy, though if Diana wants something interactive that's going to require hardware they don't have here. Most likely in the form of a teaching droid, actually, but she'll sort that out later.
Anyway. The state of the galaxy. (She pauses to get a sketchbook and some colored pencils out of the cabinet by the cot.) The galaxy looks roughly like this; this bit is the Sith empire, where they are now, this bit belongs to the hutt trade empire, and this bit is the republic, which has some kind of complicated democratic thing going on. The rest of it is the outer rim, which isn't a coherent polity on a galactic scale. The empire and the republic are - or were last she checked, but she'll be surprised if it's changed - at war; the hutts are more closely aligned with the empire but mostly neutral in a 'selling weapons to everyone' sense. The Sith started the war and can be assumed to be in the wrong about it, though it's been long enough since the war was relevant to Pradnakt's life that she's forgotten most of the details beyond that; they can get Diana a book or something on that, too.
None of these three polities are particularly morally upstanding, in Pradnakt's opinion, but the empire is arguably the worst and in any case it's the one Diana is going to have to deal with at least at first. To explain the empire first she has to explain Sith, and the Force - the Force is the part of physics that can be interacted with by some people to let them do things that look like magic; there are various methods of interaction that have various prerequisites in terms of mental state and allow for different effects, and Sith study a method called the dark side, which uses emotions - particularly negative emotions like anger and fear - to empower the effects it can create, with the side effect of also strengthening those emotions. If Diana is thinking that this sounds like an incredibly bad idea, yes, it rather is; your average Sith finds a balance that leaves them functional enough, but it's not exactly rare for them to wind up in destructive feedback loops, and the culture doesn't help. All Force sensitives - people who can interact with the Force, which is a very rare ability - discovered in the Empire are trained to be Sith, starting from early adolescence, and the emperor and entire upper government are Sith, though in practice most governance happens on a planetary level and is run by Forceblind people, and the main effect of having Sith around is that they're entirely above the law and beholden only to other Sith.
(Yes, Pradnakt is a Sith. She's been opting out of interacting with most of the empire for the last fifteen years or so for personal reasons, but she still is one. That's why she's not going to go into town unnecessarily; her mere presence terrorizes people. And reasonably so, on their part.)
Relevantly to Diana, Sith culture runs on a power-based hierarchy, with Sith always on the lookout for resources that will help them overpower or defend against their rivals. Diana will be seen as such a resource, if her powers are discovered.