Hajime Do Mon

Owner of a café and Sogo's caretaker. He was previously a researcher who worked closely with Sogo's mother Ena, but he left the profession after Ena was killed over the red crystal that possesses an enormous amount of energy. Since then, he had been running a café and raising Sogo.

[Spoiler] In episode 9, he died due to being ran through by a sword. [/Spoiler]

(Source: Wikipedia)