Tachibana Giou (祇王 橘 Giou Tachibana) is the steward at Twilight Mansion and a member of the Giou clan. He is also a supervisor of the Zweilt.
Tachibana has an upbeat personality and likes to keep the conversation going. It is also mentioned in the manga that he may be an Opast, though no one is certain of whether he was joking or being serious.
He has an odd quirk of always wearing bizarre hats and is never seen without one. He also likes giving everyone nicknames and rarely calls anyone by the given name.