In a corner of the Umamusume universe, a group of ashen-haired horse girls set up a takoyaki stand at the Solefall Faire school festival, only to find themselves in a heated culinary standoff with a neighboring yakisoba stall run by the eccentric Gold Ship and the elegant Mejiro McQueen. This is the starting premise of Umayuru: Pretty Gray, a four-episode original net animation spin-off that shifts focus away from the racetrack to celebrate the lighter, sillier side of these particular characters. The competitive escalation between the two food stands, led by Tamamo Cross and Oguri Cap on one side and Gold Ship on the other, eventually leads to an unexpected fusion dish called takoyakisoba.

The series is structured as a collection of standalone comedic vignettes, each running approximately three minutes. Following the food stall war, the second episode, Yatsuhashi Blight—the Seiun Case Files, transforms the tone into a gentle mystery parody. Seiun Sky,扮演ing the role of a great detective, and King Halo as her earnest police officer companion, travel to the remote Yatsuhashi Village to investigate a series of mysterious disappearances. The truth they uncover is far less sinister than anticipated, with the blight ultimately connected to the very mundane actions of Mejiro Bright and Tsurumaru Tsuyoshi.

The third episode, Destiny's Tide—the Turbulent Relay, brings the focus back to athletic competition, but with a chaotic twist. Biwa Hayahide gathers Hishi Miracle and several other racers for a practice run intended for the Spring Fan Fest. However, the race devolves into an unconventional relay where the participants discover there is no official finish line, leading to an unpredictable and frantic scramble. The final episode, The Art of Spectating, offers a meta look at the franchise itself as social media enthusiast Curren Chan plans a feature on the joys of watching races. She is accompanied by the passionate racing fan Chrono Genesis, as well as Loves Only You and Gran Alegria, for a day at the track where Chrono Genesis intently observes and takes detailed notes on the competitors.

The main cast is drawn entirely from the gray-coated characters of the wider Umamusume: Pretty Derby franchise, including fan favorites like the stoic eater Oguri Cap, the unpredictable Gold Ship, and the regal Mejiro McQueen. The setting rotates through familiar locations from the series, such as the school festival grounds at Tracen Academy, a quaint countryside village, and the racecourse itself. Produced by Scooter Films and released on the official PAKA TUBE! YouTube channel during Japans Golden Week holiday in 2025, Umayuru: Pretty Gray serves as a short-form, low-stakes companion piece designed to deliver quick character-focused comedy without any requirement of a larger narrative arc.