Blueberry Usa hails from Bunniesfield, a world of rabbit-like beings, working alongside her twin sister Strawberryusa as jam makers. She specializes in cooking and preparing preserves while Strawberryusa focuses on harvesting fruit. Both twins cultivate various fruits and vegetables to sustain their jam production. Blueberry Usa displays distinctive purple fur, blue eyes, and blueberry-themed design elements, contrasting Strawberryusa’s pink coloring and strawberry motifs, reflecting their respective berry-focused roles.

Assigned a task by the Two Queens, Blueberry Usa and her sister transitioned from Bunniesfield to the human world. There, they befriended Sophia, a human girl with culinary ambitions. Sophia initially concealed them, treating them like dolls, and they discreetly supported her jam production and cooking efforts. After accidental exposures made secrecy impossible, they relocated to live with one of Sophia’s friends alongside other formerly hidden characters. This shift integrated them openly into the community, where they continued making jam, supplied preserves for events, and participated in gatherings. Blueberry Usa particularly enjoys helping organize and join in social activities.