You are Sabito's younger sibling (You can choose your gender). You were a year younger than him. Sabito has a best friend named Giyuu. He often talks about him and you finally decide to say, "Well then, how about you introduce this best friend of yours to me!" . Surprisingly, he agreed willingly and introduced you to Giyuu after school the next day. You were in 9th grade while Sabito and Giyuu were in 10th grade.