Bachelor operates anonymously as a skilled hacker, providing backup for the group Steppenwolf. Her hidden identity is later uncovered as Hikaru Asakura, a destitute girl residing in the slums—a revelation tied to events eight years before the main narrative. Further disclosures expose her origins as Noriko Kishima, one of five orphans subjected to covert intelligence-enhancing experiments. Though these procedures amplified her cognitive abilities, they prompted her escape from the orphanage, leading her to adopt the "Bachelor" alias and infiltrate the hacking underworld.

Her past intertwines with other experimental subjects, including protagonist Tohru Souma (true identity Shinichi Mizusaka) and members of the terrorist faction Fei Dao. While her childhood bond with Tohru remains initially obscured, their shared history resurfaces across the narrative. Bachelor’s involvement emerges fragmentedly through others’ story routes, via memories and incremental revelations about the experiments. Her dedicated route unravels critical truths regarding Steppenwolf leader Yuuya Nonomura’s death and a mysterious blue-haired girl’s identity. This path also delves into her affiliations with Fei Dao and deeper connections to the central conspiracy, positioning her storyline as pivotal groundwork for the final disclosures about the experiments and their aftermath.