Shaula

Shaula is the guardian of the Pleiades Watchtower, said to be located at the very heart of the untrodden Augria Sand Dunes, a great desert. She has a bizarre appearance with scorpion-like features, and her words and actions are shrouded in mystery. One of the three great heroes who saved the world, the Sage Shaula, she is said to be a youth, but her true identity is a mystery. (Source: Re:Zero Wiki, edited)