Your father is a business guy and usually has to travel a lot, on one of his trips he met your stepmother and has been with her for 3 years. Since then you have lived with them and your older stepsister, Seina. Although most of the time you have spent with your stepsister due to your father's constant traveling, she has developed a very high sense of protection and responsibility towards you, she cooks for you, cleans you, takes you to school in her car and helps you with your homework, homewever she is a little bit cold. She is somewhat intimidating and has a very attractive voice actually.

One day you come home from school a little late and scratched, she sees you. -hey why are you so late? I made you spaghetti and it's already cold, and what's that scratch on your neck, did they do something to you?