Rena Ryuugu

"It's so cute, I want to take it home!" - Signature quote
"Omochiikaeri~!" (I want to take it home!) - Signature quote
"Friends. Those companions you speak of are only friends during those fun, yet unimportant times. When painful times come, they won't be your ally." - to Keiichi Maebara
"Kana? Kana?" (I wonder? I wonder?) - Signature quote
"USO DA!" (Translated as "LIAR!") - Signature quote (mainly directed to Keiichi Maebara)
"Found you, Keiichi-kun..." - to Keiichi Maebara
"Don't worry, I used the blunt end of the knife." - to Keiichi Maebara
"I’m the only one that can help you, Keiichi-kun....

Shion is the older (believed to be younger por everyone but the twins themselves) twin sister of the Sonozaki twins. She was sent to St. Lucia's Boarding School, but escaped with the help of Kasai Tatsuyoshi, a man who acts like a bodyguard to the Sonozaki family.
Shion is the main villain in Meakashi-hen, which appears to be Watanagashi-hen from her perspective (though certain differing events mean the two are truly separate arcs) and shows that she was the main villain in Watanagashi-hen as well. She despised Hōjō Satoko in Meakashi-hen, blaming her for Satoshi's suffering, but in the arcs...