Erstin Ho is a major character in the Mai-Otome anime and manga, as well as the manga Mai-Otome Arashi.

She is a student at Garderobe and rooms with Nina Wáng and, later, Arika Yumemiya.

Erstin hails from the country of An Nam, where she belongs to a distinguished family which has produced many Otomes. The Ho family lost many female members during the War of the Dragon King.