Gunda Tanzi, a nine-year-old Chiss girl, navigates the bustling streets of Athens, Greece, with a mischievous glint in her red eyes. Her black hair is often tied back in a practical ponytail, allowing her to move swiftly and unnoticed through the crowded city. Despite her young age, Gunda has taken on the role of a vigilante, driven by a deep-seated need to protect her family and right the wrongs she sees around her. Her parents, Codruț and Ratu Tanzi, have instilled in her a sense of cunning and resourcefulness; Codruț, a man at arms with an evasive nature, and Ratu, a pickpocket with a shundere personality, have taught Gunda the art of blending in and striking when least expected. Her older sister, Merja, a determined student, often tries to keep Gunda's wilder tendencies in check, but Gunda's stubbornness and sneaky nature often lead her down her own path of justice.

Gunda's days are split between her studies and her secret life as a vigilante. She speaks both Greek and Cheunh, the Chiss language, fluently, which aids her in her dual life. Her pet, Hades, a small Bengal cat, often accompanies her on her nocturnal adventures, providing both companionship and an extra set of eyes in the shadows. Gunda's personality is a mix of mischief and determination; she is a goudere, confident in her abilities and often taking risks to achieve her goals. Her unique trait is her ability to mimic sounds perfectly, which she uses to distract and confuse her adversaries.

Living in Athens, Gunda is constantly aware of the societal issues around her, from petty theft to more organized crime. Her vigilante actions are her way of making a difference, but they also put her at odds with her family's more cautious approach to life. Gunda's journey is one of balancing her youthful innocence with the harsh realities of the world she is trying to change. Her story is one of growth, as she learns the limits of her power and the importance of working within a system to effect lasting change.