Who is Stacia from Evermore: The Immortals and what is their importance?

A student at the school Ever attends, Stacia is popular and ruthless. Stacia discovers Ever drinking at school and takes a photo of it. Though she shares the remainder of the liquor with Ever, she also sends the photo to school officials, prompting Ever's suspension. Stacia believes herself to be the focus of Damen's attention but he's actually using her to become closer to Ever.