Asaka Nogiku, who also operates under the alias Neruloid Girl, is a central figure in the story. She is an Earth girl with a noticeable fondness for beer, a detail that adds a layer of ordinary, down-to-earth charm to her character. Her involvement in the central conflict begins when she is hired by the Emerald Company to test their power suit, which allows her to transform into the hero known as Neruloid Girl. As a resident, she occupies room 4 in the Cosmos House, a shared living space where she lives alongside other characters without revealing her secret identity. She becomes friends with her neighbors Suzuo and Tanpopo, even going so far as to store her beer in their refrigerator, unaware of their own hidden lives.

In her role as Neruloid Girl, Asaka is a direct rival to the protagonist, Dokkoida. Her mission is to fight Class A criminals in order to win a lucrative contract for the Emerald Company, making her a competitor in the battle for the title of top hero. Her character design reflects a theme of nature, with her appearance and abilities centered on the motif of the chrysanthemum, a traditional Japanese flower. Her hairstyle is shaped like flower petals, and her costume combines green and purple with floral patterns and leaf-like decorations on her sleeves and leggings. This theme extends to her powers, as she possesses the ability to manipulate and control plants, using them for both offensive purposes, such as capturing enemies, and supportive roles, like healing her allies.

Asaka’s personality is consistently portrayed as optimistic, cheerful, and sociable. She has a strong inclination to help others and make friends, approaching her duties as a hero with an open and enthusiastic demeanor. This kindness and empathy are key traits, as she is sensitive to the emotions of those around her and tends to make decisions based on her personal values and moral code rather than cold logic. Despite her friendly exterior, she can also be introverted and pensive at times. One of her defining struggles is her tendency to put the needs of others before her own, sometimes to her own detriment. She often prioritizes the welfare of her teammates and love interest over her own well-being, which aligns with her self-sacrificing nature.

Throughout the narrative, Asaka forms significant bonds with other characters. She develops a close working relationship with the hero Dokkoida, with whom she initially clashes as rivals. Over time, he moves from underestimating her abilities to respecting and depending on her as a reliable partner in their shared quest to uncover the true intentions of the company running the hero competition. Her relationships are not solely professional; she also harbors a romantic interest in another contestant named Beautybloom Prince, which adds a layer of light drama to her story. As a fighter, her notable abilities are entirely tied to her power suit, which grants her control over flora. She can generate vines and other plant life to restrain foes or heal wounds, making her a versatile combatant who can adapt to both aggressive and supportive roles.