Lucius "The Headmaster" Fujioka

About

The Headmaster of the school.

He was the coach of the Volleyball team when Kibisawa, Danko was still a student. He proposed the Double jump theory or simply known as the Breast Jump, where a girl uses the momentum of her breasts to either have more airtime or to add vertical to their jump. Back when Danko was still student, they had a relationship.

(Source: Chounyuu Gakuen manga & Shichinin no Mama manga)