Erstin Ho (エルスティン・ホー Erusutin Hō) is one of the main protagonists of the Mai-Otome series. She is a Coral Otome.
Erstin has blonde hair with bangs covering her forehead, and another two frames her face. Her hair reaches down to her neck, while it slightly reaches past her nape on the back. She has a little strand of hair pointing upward behind her bangs. Erstin has green eyes and large breasts.
She wears a red, sleeved dress and much like many other Coral Otome's, has a piece of cloth fashioned somewhat like an apron over her dress. The entire piece of cloth is lined by teal, and at the shoulders there are large white frills protruding. In the bosom area, it is decorated with a red, four-pointed star, and wings that appears raised underneath it. The wings also appears on the back of cloth, slightly below the nape. The cloth is secured by white ribbons at the side and she also has a collar, secured by a circular golden broach, which has a pink jewel in the center and three triangular pieces coming down from the bottom. She also wears white stockings which have a single, horizontal teal zigzag across near the top. She wears brown loafers which are secured by a strap round the ankle.