He is the secretary of Maruo Nakano and occasionally driver of the Nakano quintuplets. Ebata is said to have a professional history as a school teacher. He cares deeply for the quintuplets.
SpoilerEbata took on the pseudonym of Atabe Maruo, the quintuplets' fictitious tutor, at their favor in an attempt at making Fuutarou Uesugi their tutor again. Before this, Maruo assigned Ebata as the quintuplets' tutor after Fuutarou resigned. In the end he helps the plan of the quintuplets in bringing Fuutarou back as their tutor.