Adopted by the Nakagawa Family at a very young age, Shiba does not know who her biological parents are, nor if she has any siblings. Because the Shiba Inu breed has never been recorded to have residencies in Laurentia, the city she currently resides in, the Nakagawa Family named her as her breed itself.

Growing up in a lower-middle class family, Shiba knows how to survive with the bare minimum. As a young child, she often accompanied her older adoptive brother Akio in doing paid errands for other people. Eventually, their financial situation became more stable as they grew up, and Shiba was soon able to enjoy the simple luxuries she never had as a child.

Currently, Shiba is a high school student at Cambria University alongside her three close friends: Millie, Tonia, and Heather. She often comes by the Cooking Club, but is not an official member.

An extraverted and energetic girl, Shiba is not afraid to start conversations with just about anyone. Her positive mindset and attitude are her charms, and people tend to become amused at her antics and enjoy her company, although she can become annoying at times. However, despite her charmingly bright personality, she is comically naive and is often thought of as an airhead (most especially by Millie).

Growing up as an adopted daughter of a lower-middle class family, Shiba knows firsthand how it feels to work hard just to sustain the most basic needs. Although she has always had her cheerful demeanor ever since she was a child, it was not something she had on 24/7, having witnessed how her adoptive family struggled to make ends meet. Her family's sad atmosphere was something she never liked, and so, she started her personal goal of helping everyone to be happier.

One thing surprising to everyone else is Shiba being quite emotionally intelligent. Though not the best at giving advices, she is always willing to listen eagerly and to help anyone out in order to make them happy. On the contrary, she is not very bright with her academics, and always turns to her friends to ask for help with schoolwork. Mathematics, in particular, is her weakest suit, once scoring a meager 13% of the questions correctly in a test.