lightreads

Naturally when you asked this, my mind went blank. But after sleeping on it, I think YA and middle grade can be particularly good at this. Ironic since I barely ever read either these days. But see Mars Evacuees (which arguably could fulfill your preferred mode too, depending on how you approach the text) or a lot of Ursula Vernon's stuff, like Castle Hangnail. And on the adult side, Girl Genius (I've read the novelizations, but I hear they stick very close to the webcomic).

Same question back at you for heavier books with flashes of lightness.