Haru's grandfather (whose real name is unknown) is Haru only living relatives after Haru parents died from a bug attack. He works along side Haru at the Four Seasons.
Haru's grandfather wear a traditional Japanese outfit and has no hair.
Haru's grandfather seem to be a warm loving grandfather to his granddaughter and tease her when she has feelings for Jinbei.
Not much is known about his past but when Haru's parent died, he look after Haru and the family business.
Haru's grandfather, being an ordinary human, possesses no superhuman abilities.