TV-Series
Description
Kasumi Yashiro, originally designated Trista Shestina (Триста Шестая), is Alternative III's genetically engineered esper, the 306th specimen of the sixth generation. Her designation incorporates a Russian numerical pun ("trista shest" meaning 306). She possesses distinct physical traits: waist-length white hair, grey eyes, pale skin, and a height of 133 cm. Her modified genome prevents physical maturation beyond a young teenager to preserve her psychic abilities.
She resides within Yokohama Base's B-19 floor in a room housing a preserved brain within a glowing cylinder. Her role involves communicating psychically with this brain, later identified as Kagami Sumika, interpreting and projecting its thoughts. Initially timid, distrustful, and taciturn, she exhibits minimal social interaction and engages in repetitive activities like cleaning and sketching. Early interactions with Shirogane Takeru are marked by shyness, though she gradually adopts mannerisms reminiscent of Sumika, such as waking Takeru daily.
Her abilities prove critical to Alternative IV and Professor Kouzuki Yuuko's experiments. She maintains a psychic link to Takeru during causality conduction, observing his experiences in other timelines and preserving his memories through detailed drawings to anchor his return. This demanding task requires intense concentration, leading to prolonged isolation. Her connection to Sumika's consciousness within the cylinder deepens, allowing her to retrieve Sumika's identity and form an emotional bond. Though describing her relationship with Yuuko as impersonal—defined by "interest and disinterest"—she operates under Yuuko's direction for project tasks.
Emotionally isolated due to her artificial origins and feared by fellow espers, she adopts fragmented memories from both Sumika and Takeru to counter loneliness. This leads to profound shame upon the revelation of her origins. Takeru's promise to create new memories with her and his gift of a conch shell (symbolizing a future beach visit) provide emotional solace. Her devotion peaks during the 00 Unit tuning, where she selflessly advocates for Sumika's reunion with Takeru, prioritizing their happiness despite her own unspoken affection. Following Operation Ouka, she explains the time loop mechanism tied to Sumika's consciousness, enabling Takeru's return to his original world. During their farewell, she implies her ability to observe him across realities and, under specific conditions, confesses her love if Mitsurugi Meiya is not his primary romantic connection.
In *Altered Fable*, she appears as a Russian transfer student in Takeru's world, moving in with Sumika as her roommate. Though still reserved, she bonds inseparably with Sumika and interacts comfortably with Takeru. Her memory's status regarding Alternative's events remains ambiguous; an encounter with Takeru in *Final Extra* causes her to collapse into tears upon seeing him, suggesting potential retained memories or residual emotional echoes from that timeline.
Her later canonical role sees her presiding over Earth as the Union of Mankind's first superintendent by 2049, leveraging genetic engineering to retain her youth.
She resides within Yokohama Base's B-19 floor in a room housing a preserved brain within a glowing cylinder. Her role involves communicating psychically with this brain, later identified as Kagami Sumika, interpreting and projecting its thoughts. Initially timid, distrustful, and taciturn, she exhibits minimal social interaction and engages in repetitive activities like cleaning and sketching. Early interactions with Shirogane Takeru are marked by shyness, though she gradually adopts mannerisms reminiscent of Sumika, such as waking Takeru daily.
Her abilities prove critical to Alternative IV and Professor Kouzuki Yuuko's experiments. She maintains a psychic link to Takeru during causality conduction, observing his experiences in other timelines and preserving his memories through detailed drawings to anchor his return. This demanding task requires intense concentration, leading to prolonged isolation. Her connection to Sumika's consciousness within the cylinder deepens, allowing her to retrieve Sumika's identity and form an emotional bond. Though describing her relationship with Yuuko as impersonal—defined by "interest and disinterest"—she operates under Yuuko's direction for project tasks.
Emotionally isolated due to her artificial origins and feared by fellow espers, she adopts fragmented memories from both Sumika and Takeru to counter loneliness. This leads to profound shame upon the revelation of her origins. Takeru's promise to create new memories with her and his gift of a conch shell (symbolizing a future beach visit) provide emotional solace. Her devotion peaks during the 00 Unit tuning, where she selflessly advocates for Sumika's reunion with Takeru, prioritizing their happiness despite her own unspoken affection. Following Operation Ouka, she explains the time loop mechanism tied to Sumika's consciousness, enabling Takeru's return to his original world. During their farewell, she implies her ability to observe him across realities and, under specific conditions, confesses her love if Mitsurugi Meiya is not his primary romantic connection.
In *Altered Fable*, she appears as a Russian transfer student in Takeru's world, moving in with Sumika as her roommate. Though still reserved, she bonds inseparably with Sumika and interacts comfortably with Takeru. Her memory's status regarding Alternative's events remains ambiguous; an encounter with Takeru in *Final Extra* causes her to collapse into tears upon seeing him, suggesting potential retained memories or residual emotional echoes from that timeline.
Her later canonical role sees her presiding over Earth as the Union of Mankind's first superintendent by 2049, leveraging genetic engineering to retain her youth.