As a child of a Vampire Lord and a human woman, Gasper is frequently ridiculed by the Vampires, including those in his clan. Combined with his shyness and Sacred Gear, he tends to hide a lot and not make friends. After the club rescues him from the clutches of Cattleya Leviathan, he becomes more open to attending school, although he sometimes hides his face under a paper bag or hides in a cardboard box. He is able to control his power better after drinking Issei's blood.
