TV-Series
Description
Shion Sonozaki, originally born as the elder twin named "Mion," swapped identities with her sister during the ceremony designating the Sonozaki family heir. This resulted in her becoming "Shion," excluded from succession and sent to St. Lucia's boarding school. She escaped in 1982 with help from bodyguard Tatsuyoshi Kasai, relocating to Okinomiya. There, she worked as an Angel Mort waitress and became assistant manager for the Hinamizawa Fighters baseball team.

Her St. Lucia education gave Shion a refined surface, yet she possessed a shrewd, manipulative, and rebellious core. She despised the school, calling it a "factory for manufacturing ladies," and engineered her escape by studying security systems and spreading rumors of an affair with a teacher. She enjoyed mapping out elaborate schemes, like ruining delinquents' reputations for amusement. She developed deep affection for Hōjō Satoshi after he defended her from harassers, though he mistook her for Mion. This fueled intense jealousy towards Satoshi's sister, Satoko, whom Shion blamed for his suffering.

In *Meakashi-hen*, Hinamizawa Syndrome, paranoia, and envy fractured Shion's mind. She resented Mion's heir status, Rika's position as Oyashiro-sama's reincarnation, and Satoshi's devotion to Satoko. Falsely believing the Sonozaki family "demoned away" Satoshi, she impersonated Mion, infiltrated the family estate, and murdered villagers including her grandmother Oryō and village head Kimiyoshi. Her rampage ended with the deaths of Rika and Satoko before her suicide.

Later arcs like *Minagoroshi-hen* and *Matsuribayashi-hen* showed Shion's redemption. Honoring Satoshi's request to protect Satoko, she formed a sisterly bond, risking her life to shield Satoko from abuse. She threatened Satoko's abusive uncle, Teppei, but cooperated with Keiichi to pursue legal action. During the Yamainu paramilitary confrontation, she used non-lethal tactics like a stun gun and sniper rifle to disarm opponents, demonstrating improved emotional control and rejecting past violence. This shift highlighted her capacity for growth when prioritizing others' safety.

In *Higurashi Gou* and *Sotsu*, Shion's role diverged. In the anime's *Watadamashi-hen*/*Wataakashi-hen*, Mion—injected with Hinamizawa Syndrome by Satoko—accidentally killed Shion during a psychotic episode, briefly expressing remorse. Conversely, the manga (*Meguri*) depicted Shion as the perpetrator: after Mion died accidentally, Shion assumed her identity and committed murders to protect Keiichi, believing it aligned with Mion's wishes, emphasizing her latent volatility.

Post-*Matsuribayashi-hen*, *Higurashi no Naku Koro ni Rei* (set 35 years later) reveals Shion married Satoshi Hōjō. Her design in later media often included her St. Lucia uniform, symbolizing her connection to Satoko, whom she doted on as "Nee-nee."

Physically identical to Mion, Shion distinguished herself with a half-ponytail tied by a yellow ribbon. She wore her St. Lucia uniform during school and casual outfits like a sleeveless striped turtleneck and black skirt otherwise. Her weapon of choice was a stun gun provided by Kasai.