Uma is a princess from the Netherworld who relocates to the human world with three other princesses. They reside together in Garakuta House, a makeshift treehouse complex within the fictional Japanese city of Hikarigaoka. Identified as a witch, her spellcasting is limited due to her classification as a "third rate alchemist."

She consistently displays a happy and cheerful personality, finding genuine joy in exploring the human world. When she makes discoveries about human life or customs, she often points them out proudly and quickly to her companions. However, she is typically the last in the group to notice or understand these new elements, leading to disappointment when others grasp concepts faster. Her naivety extends to social situations, sometimes resulting in obliviousness to implications or nuances.

Her magical abilities are unreliable, with attempts at casting spells frequently resulting in mishaps, often accompanied by an unintended lifting of her skirt. She possesses two rabbit-like companions: a peach-colored one named Jun and a black one named Tan. These creatures can spin their ears to fly, use their ear tips like hands, and occasionally float. Tan also possesses the ability to transform into Uma's witch hat.

Visually, her design incorporates multiple rabbit-themed elements, including her hairstyle which occasionally moves on its own, her rabbit companions, and a carrot-shaped cushion she uses for sleeping. Outside of practicing magic, her interests include reading romance manga.