At first, she was a quiet and reserved girl who rarely talks to anyone and doesn't smile much, and lacked confidence. However, after a horrific event involving Kamoshida's sexual advances towards her, she nearly committed suicide. Shiho was rescued by Ann Takamaki and Ren Amamiya, who took her to the Metaverse. Eventually, she confronted Kamoshida's Shadow, and unlocked her Persona, Hester Prynne. Afterwards, she joined the Phantom Thieves, wielding a meteor hammer and an Uzi.