So I am working on reading all/as many books to stardust as possible. I know there are some items on this site that have multiple uses and I'm worried that I could possibly read a book to my pet and have something happen that I'd much rather avoid.

I know this seems like a silly thing to be worried about 'cause I assume this won't happen but I figured it'd be best to just ask.

There are no books that will affect your pet if you read them to her. Some books are also stat boosters, those will have a Use option on them, so you'll want to be careful with that. As long as you do use the read option though, you're fine (and I don't know of any books off hand that would have a negative effect on your pet anyway)

As long as you click "Read to" you should be fine. I can't think of anything off hand that would change your pet (other than giving them stats).

Some things, like the cash shop research notes or the Molten Summoning Tome can be "used" to summon battle opponents as well as being read. But even if you do summon the battle opponent, it won't hurt or change your pet unless you go battle it.

Things like the Tome of Endurance, can be used to give your pet Health, or you can choose to read it.

Things like the Tome of Fire can not be read to your pets, only used on them to give them stats.

Then there are a few non-book items that can be read to your pets, like the Geeky Fruit.