Muir Castreia

ミュア・カストレイア

A young Gabranth who thinks of Hiiro as an older brother. [Spoiler] Muir has awakened to her Binding, by exchanging a contract with the Spirit of Thunder. In order to train to the level of holding her own as an adventurer, Muir, alongside Arnold, trained for six months under Rarashik. [/Spoiler] (Source: Konjiki no Word Master Wikia)