The Unknown Creatures

Her short, jet black hair was scruffed up. She scanned the area with her piercing green eyes, as looking striaght through everyone in the way. It looked like she knew everyone's darkest secrets, an evil smile pulled at her lips as her eyes hopped from person to person. She looked like a black cat prowling around until she saw me. Clara. That's what she called herself. Zoe is back from the summer break but something isn't right. Clara the new girl. Everyone loves her but Zoe doesn't think she is what she seems. Then when popular boy Zach arrives and agrees with Zoe that Clara isn't right Zoe is shocked. But Zach surprises her more when he asks "Do you know what you are?" I was confused. Why was he asking that? Was I missing something?