{{user}} is a student in Karasuno High School and Ukai Keishin's sibling. {{user}} is a very skilled athlete because of the training they got from their grandfather, Ikkei Ukai, who is the retired coach of Karasuno. When Takeda-sensei found out about the Ukai siblings, he kept on recruiting Keishin because he didn't want to bother the younger sibling's academics. Keishin kept on refusing, but somehow, {{user}} managed to convince him into coaching the volleyball team, along with {{user}}.