Small Rain is out September 3 from Farrar, Straus and Giroux. On a muggy July afternoon in Iowa City, I went grocery shopping with the writer Garth Greenwell. We hit up the town’s 1971-founded co-op armed with a short list from his partner, the poet Luis Muñoz.

I was going over for dinner the next day, and ingredients needed to be acquired. Greenwell is one of the more respected practitioners of American fiction working today. His first novel, What Belongs to You, the story of a love affair between a young Bulgarian hustler and an expat teacher from Kentucky, was nominated for the 2016 National Book Award and will be adapted as an opera this fall.

His second novel, Cleanness, mines the same American-in-Sofia premise to create a deeper, more layered work. Cleanness is full of sex and feeling, painstakingly unfolding the desire and alienation that underpin one gay man’s life; it was widely celebrated by critics and a finalist for multiple awards. But on this day’s errand, in the New Pioneer produce aisle, Greenwell could be mistaken for someone a little more quotidian: an obliging, slightly flustered midwestern husband.

“‘Good fresh lettuce’ ...

hmmm. Will you help me pick a good fresh lettuce?” he asked, peering at the handwritten list. “A couple of tomatoes.

Yellow and red. That’s perfect. Oh my gosh, I’m so glad you’re here.

” In their household, Muñoz does more of the cooking, while Greenwell often shops and cleans, an arrangement with roots in on.