Kasane Kujiragi

Kasane Kujiragi is a wielder of Saika. Although mentioned in passing in previous volumes, she first appears in person in volume 10 as Jinnai Yodogiri's secretary and apparent niece and is later revealed to be the ringleader behind the organization that collectively operates under Yodogiri's name, thus making her the main antagonist of Durarara!!x2.