Oooo… a book that comforts me… honestly there are so many!
I think probably my ultimate go-to comfort book would have to be Good Omens. I know it really well, it’s funny, and it’s just such a satisfying read. ^_^ I can let it fall open anywhere among its pages and instantly know where I am and there is no part of that book that I don’t like. ^_^
Also, pretty much anything by Anne Bishop. Her books are dark and disturbing, but also funny and with SUCH rich world building. It’s very cathartic for meto read certain parts of certain of her books, which is comfort of a different kind, I think. ^_^