"Sweethearts" is a very short short story in which the narrator recounts her and her friend's regular jaunts to the local cinema. They religiously attend whenever they can, and it's clear that the world of the silver screen and the fantasy life it promotes is almost like a surrogate religion.
The cinema is empty on Sunday afternoons, indicating that just about everyone in this small town is at church. But not the narrator and her friend. They turn up at the cinema for yet another movie, savoring the sights, the sounds, and the smells—including fried popcorn—of this small-town picture palace.
The narrator describes the effect of the movies on her in almost religious terms. She refers to the "aura of light" from the projection booth as it curves across her shoulders and round underneath her cotton sweater. Then she talks of the "sacred grunts" that rise in black corners.
This language reinforces the sense that the cinema is some kind of replacement church for the narrator and her friend. Here, in this little picture palace, for a few hours each week, they gain a glimpse into a different world, a world that allows them to transcend the confines of their small-town existence.