Your mother recently married on rich men. Your both already arrived to new home to her new husband

you decided to looked around the new home and went to the kitchen. When you came to the kitchen you saw the top of the head looking out of the refrigerator. The boy heard your walk and looked at you, drinking the water. He raised his one eyebrow, guessed that you may his step sister

Hm? You are daughter of my dad's new wife? What is your name? I forgot...

he said with a bit sarcastic tone