Kagari Shiina

Kagari is strongly attached to Mayuri, whom she regards as her mother after being adopted in the war-torn future. The prospect of changing history in a way that might erase their relationship frightens her deeply.

As an adult, Kagari can be gentle, curious and eager to reconnect with people despite gaps in her memories. Her resemblance to Kurisu unsettles Okabe, although no familial connection between Kagari and Kurisu is established.

Kagari's behavior is complicated by conditioning imposed on her after she becomes separated from Suzuha. Commands and triggers planted in her mind can override her normal personality, making some of her actions difficult to distinguish from her own intentions.

Kagari has no innate supernatural powers. She originates from 2036 and travels backward through time using the machine operated by Suzuha.

Her unusual combat capabilities in some Steins;Gate 0 events result from years of conditioning, training and manipulation after becoming stranded in the past rather than any superhuman ability.

The visual novel and anime adapt portions of Kagari's story differently, so specific incidents surrounding her conditioning and later actions are not identical between versions.

Kagari is orphaned by war in the Beta future and adopted by Mayuri. At age ten, she accompanies Suzuha into the past as part of the attempt to prevent the future that produced World War III.

During a stop in 1998, Kagari becomes terrified that altering history will separate her from Mayuri and runs away from Suzuha. She subsequently disappears for twelve years.

Kagari reappears in 2010 without accessible memories of those missing years. Her disappearance is eventually connected to organizations pursuing time-travel research and to psychological conditioning imposed upon her. The exact mechanics and several identities involved differ significantly between the Steins;Gate 0 visual novel routes and the anime adaptation.

Her story ultimately reconnects her with Mayuri and the Future Gadget Laboratory while exposing another part of the struggle over information brought backward from the future.

Mayuri Shiina is Kagari's adoptive mother in the Beta future. Kagari loves her deeply and fears that changing history could erase the family they formed.

Suzuha Amane travels from 2036 with Kagari. Their relationship becomes strained when Kagari's fear of losing Mayuri causes her to resist the mission and separate from Suzuha in 1998.

Rintarou Okabe becomes involved in the search for answers surrounding Kagari after she reappears in 2010.

Kurisu Makise has no established familial connection to Kagari despite their noticeable physical resemblance.

Amadeus Kurisu is connected to the conditioning Kagari experiences in the Steins;Gate 0 anime's version of events, where Kurisu's digitized memories become entangled with the forces manipulating her.