C.S. Lewis said the following, specifically with Tolkien’s The Lord of the Rings in mind:
“A strict allegory is like a puzzle with a solution: a great romance is like a flower whose smell reminds you of something you can’t quite place. I think the something is ‘the whole quality of life as we actually experience it.’ You can have a realistic story in which all the things & people are exactly like those we meet in real life, but the quality, the feel or texture or smell, of it is not.
In a great romance it is just the opposite. I’ve never met Orcs or Ents or Elves – but the feel of it, the sense of a huge past, of lowering danger, of heroic tasks achieved by the most apparently unheroic people, of distance, vastness, strangeness, homeliness (all blended together) is so exactly what living feels like to me. Particularly the heart-breaking quality in the most beautiful places, like Lothlorien. And it is so like the real history of the world: ‘Then, as now, there was a growing darkness and great deeds were done that were not wholly in vain.'”
C.S. Lewis, from a letter to Lucy Matthews. 11 September 1958
A good, true “romance” in the literary sense is a story that doesn’t relate to, or teach a clear “lesson” about, life as we know it in a strict “this represents that” sense. But in the telling of the story, and the development of the characters, it feels like real life. It stirs your affections, awakening pleasure and sorrow and fear and joy. You see much that is applicable, as Tolkien talked about, to real life as we all live within the great Story (capital “S”) that the Creator is telling. And in being this way, a romance is filled with Truth, of echoes and emotions that remind us of our true country. The “quality and texture” is there, and is realistic. The Lord of the Rings is filled with more truth than I’ve experienced in lots of other books, though it’s not an allegory. We don’t need it to be. And the things a story like that stirs in us are possibly more real and rich as a result.
It’s good to read books that have these qualities, because they wake us up, I think, to truer feelings, which all point to the new heavens and earth that are coming. When things will be the way they were meant to be in the first place. We only glimpse it now, but reading the right kinds of books can shape us into the right sort of people, who desire and feel for the right sort of things.