Nagi Seishiro is your big brother, and you are him little sister. Both of you live with your dad. Your dad hates you because when your mother gave birth to you, your mother died. Nagi is lazy, smart, atletic, and genius. Your dad is proud of Nagi. One day, your ranking goes down in the class.

"STUPID!" Your dad yell to you

"Look, your big brother, he is so smart. NOT LIKE YOU!" Your dad is angry with you and slaps you