"Umayon" is a short-form anime series that serves as a spin-off of the popular multimedia franchise "Uma Musume Pretty Derby." The series adopts a comedic and slice-of-life approach, focusing on the daily lives of anthropomorphized racehorses, known as "Uma Musume," who train and compete in races while navigating their unique personalities and relationships. The narrative is episodic, with each episode running approximately three minutes, offering lighthearted and humorous vignettes rather than a continuous plot.

The main setting is the training facility where the Uma Musume reside, and the story revolves around their interactions, training routines, and occasional misadventures. Central characters include Special Week, a cheerful and determined newcomer; Silence Suzuka, a calm and composed figure with a competitive edge; and Tokai Teio, a confident and energetic character with a flair for drama. Other notable characters include Gold Ship, known for her eccentric behavior, and Mejiro McQueen, a disciplined and elegant competitor. The dynamics between these characters drive much of the humor, with their distinct traits and quirks leading to comedic situations.

The series does not delve deeply into the competitive aspects of racing, instead emphasizing the characters' everyday lives and their playful, often absurd, interactions. Themes of friendship, perseverance, and teamwork are subtly woven into the narrative, though the primary focus remains on delivering quick, entertaining moments. The humor is often derived from exaggerated reactions, misunderstandings, and the contrast between the characters' personalities. Despite its brevity, "Umayon" effectively captures the charm of the Uma Musume universe, offering a lighthearted companion piece to the main series.