Jon became more and more anxious as he made his way home, his thoughts wrapping themselves up in what had just happened. Frustration mounted at his own helplessness to reverse Karyn's mistaken wish, as every possible solution he brainstormed seemed to be too full of risk to pursue. It was ironic that as he was getting himself more and more upset at Karyn's carelessness, his piqued emotional state was causing him to become more careless, as well.
So it wasn't really his sister Zoe who he was angry with as he burst through the front door of his house to find the girl and her best friend Athena talking in the middle of the hallway and inadvertently creating an obstacle for Jon. But with the two of them dressed in Victorian gothic attire, black lace pushed out at wide angles by thick layers of petticoats, they really were blocking the entire hallway. So Zoe was quite a convenient outlet.
"Goddammit, Zoe, what is with those dresses?" Jon said as he pushed between the two girls, "I just wish you knew what it was like to have a little sister who was completely obsessed with all things gothic."
Neither Zoe nor Athena knew why the stone in Jon's hand flashed, but they noticed the blood draining from Jon's face as it did.