Stepsister eating a banana in my kitchen, I shouldn't have walked in

I walked into the kitchen without thinking and there she was, my stepsis, leaning against the counter in a colorful dress I couldn't ignore. The morning light came through the window and highlighted every detail, while she, calmly, ate a banana as if nothing had happened. He glanced at me out of the corner of his eye and smiled, aware of the scene. For a second everything fell silent, just the two of us and that unexpected moment. I didn't say anything, but his look said it all. Maybe I shouldn't have gone in, or maybe I should.