It was the first Tuesday of the month, which meant two things at Cedar Grove Public Library. The Mystery Book Club met in Meeting Room B, and Nancy, the librarian, made her please-don’t-let-me-die-here espresso in the staff room.

Nancy wasn’t into fancy brewing. She liked her coffee dark, fast, and with enough bitterness to scare away the teenage loiterers. That morning, she used the mysterious beans left behind by the college intern who wore too many rings and once claimed to be a warlock in his off-hours. She scooped. She brewed. She sipped.

That’s when the library’s Dewey Decimal numbers began to hum.

At first, Nancy thought it was a truck outside, but then she saw it. A translucent goat with glowing red eyes and smoke trailing from its hooves was slowly pacing between Supernatural Folklore and Cookbooks.

The goat bleated and every cookbook fell off the shelf.

Nancy sipped again.

The goat trotted over, nudged her ankle affectionately, then headbutted a returning patron holding an overdue DVD of Twilight: Breaking Dawn Part 2.

“Oh,” Nancy whispered. “It’s mine.”

The spectral goat, which she soon named Macchiato, proved fiercely loyal to Nancy and the library. It glared at anyone who dog-eared pages. It chased out teenagers filming social media videos near the encyclopedias. It even ate an entire printer cord in the defence of silence.

Patrons soon began coming just to see the ghost goat.

“We don’t allow emotional support animals,” Nancy told a reporter, “but this one supports library policy.”

Rumors spread and people whispered about the Goat Guardian of Cedar Grove, a paranormal protector who only appeared when someone brewed unholy espresso during budget cuts.

Nancy tried switching to tea once.

Macchiato peed ghost fire on the romance section.

Lesson learned.