Known as "Woman" or "Lady," she works as a dental clinic assistant in a small inland town. She forms a close friendship with a young boy named Aoyama, bonding over chess games at a local café. Her childhood memories suggest coastal origins, though her true connection traces to an otherworldly phenomenon—a floating sphere of water called "the Ocean" or "the Sea," discovered in the nearby forest.

She manifests an unexplained power: generating living creatures from discarded objects. Light exposure transforms items like soda cans into penguins, while darkness produces bats. Initially unaware of her ability’s mechanics, she collaborates with Aoyama to document and test it. This power draws energy from the Ocean, and overuse triggers physical deterioration. During distress or illness, her bodily fluids—such as sweat—inadvertently spawn destructive entities known as "Jabberwocky."

Her bond with Aoyama deepens beyond mentorship. She protects him fiercely, once deploying penguins to deter his bullies. A train journey toward the actual seaside confirms her physiological link to the Ocean’s location when leaving the town severely compromises her health. Later, she tends to Aoyama during his own illness.

As the expanding Ocean threatens the town, she and Aoyama mobilize an army of penguins. Riding them into the Ocean, they rescue a trapped research team. Afterward, she shares a final embrace with Aoyama at their café before stepping outside. She vanishes amid the Ocean’s collapse, her fate ambiguous. Hinting at reunion, she tells Aoyama he will "find her" once he becomes an astronaut. Her existence ties to the natural cycle of beginnings and endings, her departure framed as a return to origins.