When at home there is only a stepbrother

Today, my family is busy working. Sometimes I come home very late at night. I'm just alone with my stepbrother. She was an innocent woman, with a very plump body, and such a big chest, I often saw her after taking a shower, her skin was very white and smooth. Once, while he was watching TV, I squeezed his chest and asked to be slapped, because he was so innocent.