Ashise is the second-born child and eldest daughter in the central family of the anime Frankenstein Family. At sixteen years old, she is a genetic hybrid who possesses the combined traits of a human and a plant. This unique biological makeup is the direct result of experiments conducted by her parents, both of whom are scientists who modified their own children. Unlike her younger brother Tanis, Ashise was not born a typical human and her body reflects the unconventional upbringing the siblings experienced while living in seclusion on an isolated island.

In terms of personality, Ashise is characterized by an optimistic and open-minded nature. She is generally easygoing and rarely engages in conflict with others, preferring to maintain a peaceful and harmonious atmosphere. This gentle disposition makes her a stabilizing presence within the group of siblings, who each cope with their unusual circumstances in different ways. Despite the challenges of being a hybrid and the social isolation the family faces, she does not appear to harbor resentment or bitterness about her condition.

Ashise's primary motivations are closely tied to her family. As one of the older siblings, she shares a bond with her brothers and sisters as they navigate a world that is unfamiliar to them. Following the arrest of their parents, the siblings are relocated to a new island where they must learn to interact with normal society under the guidance of Tanis, the only unmodified child and a genius. While Tanis works to find a way for them to appear normal and blend in, Ashise plays a key role in the family unit through her supportive and caring nature. Her role in the story is that of an elder sister who helps maintain the group's cohesion, relying on her strong relationships to overcome the obstacles they encounter.

Her most significant relationship is with her twin sister, Aisley, who is a spider-human hybrid. The two share an exceptionally close bond, described as getting along very well. This connection is a cornerstone of Ashise's character, as the sisters support each other through the trials of their daily lives. She also interacts closely with her other siblings: Snow, a dog-human hybrid; Suishi, a mind-reader; and the aforementioned Tanis, the young genius who acts as the family's leader and protector.

Regarding character development, Ashise learns to adapt to life outside the laboratory alongside her family. The narrative focuses on the group's collective effort to understand societal norms and find their place in the world. While Tanis struggles with the pressure of keeping everyone safe and hidden, Ashise's development is more centered on embracing her identity and her relationships. Her arc involves the process of integrating into a community that may not readily accept her, all while maintaining her characteristic optimism.

Ashise possesses several notable abilities derived from her plant-based genetic modification. Her primary power allows her to grow any kind of plant from her body at will, giving her a unique and versatile skill set. Furthermore, her plant physiology alters her basic biological needs. Unlike ordinary humans, she does not require food for sustenance; instead, she can survive and gain energy simply by absorbing sunlight, much like a photosynthetic plant. This ability sets her apart from her siblings and reinforces her identity as a plant-human hybrid. She is also described as being a capable fighter when the situation demands it, using her powers to defend her family.