Among Others, the 2011 novel from Montreal-based Welsh writer Jo Walton, was something of a delightful oddity. A fantasy novel masquerading as a Bildungsroman, it was steeped in a love of reading and an acknowledgement of the way fiction can shape a life and consciousness. It was, ultimately, a book about books; that it won both the Hugo and Nebula awards is a testament not only to Walton’s impressive skills as a writer, but to her lifelong investment as a reader, and a rereader.

The act of rereading, as Walton writes in the introductory essay to What Makes this Book so Great?, her new non-fiction collection, is one aspect of her “ideal relationship with a book”: “I will read it for the first time entirely unspoiled. I won’t know anything whatsoever about it, it will be wonderful, it will be exciting and layered and complex and I will be excited by it, and I will re-read it every year or so for the rest of my life, discovering more about it every time, and every time remembering the circumstances in which I first read it.” Of course, she goes on to write, “this ideal relationship doesn’t always work out.”

What Makes this Book so Great follows two-and-a-half years of Walton’s rereading. The book gathers 130 mini-essays, originally appearing on the blog of her publisher, Tor. Because of their origin, the pieces are casual and conversational rather than formal. They do not, as Walton takes pains to point out, constitute reviews or criticism: “there’s no impersonality here, no attempt at objectivity.”

This is, perhaps, the book’s greatest strength. Over the course of the volume, one is not only reminded of (or introduced to) a wealth of different works, but comes to know Walton as a reader: her concerns, foibles, likes, and dislikes. Issues such as gender and sexual politics recur, but one also stumbles across more specific concerns: “I wouldn’t care at all about people believing in the Singularity, any more than I care about them believing in the Great Pumpkin, if it wasn’t doing harm to SF for everyone to be tiptoeing around it all the time.”

Walton’s collection is unapologetically an enthusiast’s book. To read Walton rereading is to immerse oneself in both the range of SF and one reader’s peculiarities. Naturally, this is not without problems. If one hasn’t read Steven Brust’s Dragaera books, for example, one essay might serve as a good introduction; individual essays on more than a dozen of his series novels will likely be ignored. Balancing this geekery are thought-provoking and perhaps unexpected standalone pieces on – to pluck a few at random – George Eliot, John Fowles, and J.R.R. Tolkien.

In addition to positioning her as a reader, What Makes this Book so Great serves as something of a backdrop for Walton’s new novel. In her essay on Iain Banks’s The Crow Road, Walton wonders why more SF authors don’t write in a manner closer to Banks’s mainstream fiction. Why aren’t there more “SF stories that are about people but informed with the history that is going on around them”?

My Real Children reads like her answer to that question. The novel begins in 2015. At almost 90 years old, Patricia Cowan is, in the words of her nursing-home care workers, “very confused.” Her confusion, however, does not result from old age alone. Cowan, it turns out, is caught between two worlds. “She had four children, or three…. She could remember things that couldn’t simultaneously be true. She remembered Kennedy being assassinated and she remembered him declining to run again after the Cuban missile exchange.”

Cowan isn’t confused. In 1949 she made a choice that cleaved her life in two, “creating” two distinct women, Pat and Trish, whose memories the old woman shuttles in and out of. My Real Children follows both of those lives, interweaving their very different developments, giving neither primacy, investing both with emotional weight and narrative drive. It’s an impressive feat, and a deceptive one. At first glance, one is reminded of the movie Sliding Doors, in which one character is followed along diverging paths, but Walton digs deeper. It’s not just that Cowan is living two lives; she is actually living in two alternate histories, neither of which is the “true” world Walton’s readers inhabit. In one narrative stream, Kennedy is not assassinated; in the other, he is, but with a bomb.

It is unclear whether Walton has wrapped a literary novel around SF tropes, or crafted a subtle genre novel featuring achingly beautiful prose and carefully crafted characters. Ultimately, it doesn’t matter. Walton has created an SF story focused on characters and informed by the world around them. My Real Children is the rarest sort of novel – one that transcends genre. It is a book that, one surmises, will be eagerly reread as the years pass.