Four Faces, Wobbly Mirror by Chester Eagle

Simple yet elusive, down to earth yet haunting, Four Faces, Wobbly Mirror concerns two apparently well-matched couples who, at the outset of the story, have little more than a dinner-party acquaintance with each other. Yet a crossover of affections takes place between the partners and two new relationships develop – one inhibited but passionate, the other more freely sexual though still bound by personal limitations.