The Chronicles of Master Li and Number Ten Ox, by Barry Hughart
Any and all of The Culture novels
The Hobbit, and TLotR trilogy. Used to read them every summer, for about twenty years.
Armor, by John Steakley. Sadly, the only sci-fi novel he ever wrote, and one of only two books he ever authored, IIRC.
The Jean le Flambeur trilogy by Hannu Rajaniemi, which is on my list to read again this year.
A Wizard of Earthsea trilogy, which I'm about to read again as soon as my wife finished them.
The Chronicles of Narnia, which I used to read frequently when younger. I'm almost afraid to pick them up again now, for fear that they won't be as good (for an adult) as I remember.
I plan to reread all Clive Barker novels a second time, at some point in my life. His prose is just so unique and has an effortless beauty about it that I've yet to find in another author.
Plot can only really draw you in once... when you already know what happens in a story it doesn't have the same pull it had the first time. But prose has a lasting appeal, one that can be revisited. The indescribable quality of the way that words can make you feel is unique to the relationship between reader and writer.
The book is basically Tolkien+Disney, it is aimed at a kid audience but it tackles some heavy topics that adults will enjoy, its great because it tackles metaphysics a lot in ways that are interesting for all ages.
I re-read it a few times already, and even though written in the 50s it holds up quite well (except for the total absence of computers). Its a brilliant read. Edit: to clarify, I meant the societal trends he projected are quite fascinating. Also the transition to a post scarcity society. It's not very prophetic obviously. :)
The Practice Effect by David Brin. It's an isekai (it's not anime, but it's an isekai) where things get MORE useful when you use them, reversing entropy.
Sentenced to Prism. MC is sent on a mission to a world inhabited by silicate based life forms. Shenanigans ensue. Mildly autistic coded MC.
Resurrection Inc. The dead are resurrected as mindless zombie robots. Sometimes it goes wrong and the dead regain their memories. The MC does. Hijinks ensue.
edit - more
Mistborn Chronicles - an orphan gets super powers in a very messed up world. A group recruits her for a heist.
I'm a big rereader in general, but occasionally a book will grab me so hard that I finish it & begin again right away. I've had two of those in the past year:
Also, I keep meaning to make time to re-read some required reading books from HS: Where the Red Fern Grows, Call of the Wild, Flowers for Algernon. It's probably all going to be painfully YA, but I've thought about the stories often over my life, and they deserve a re-read.
The Diary of Edward the Hamster 1990–1990
its short so suitible for a quick reread & even for people who dont like books
its like a childbook in the amount of text but more for adults
Synchronicity because I just put a book on hold at the library that I'm going to read again. It is called "Galileo's Dream" by Kim Stanley Robinson, and it's half historical fiction, half science fiction about: "what if future humans living on the Galilean moons of Jupiter discovered time travel and needed Galileo's help?"