Sara Valestein is the instructor for Class VII, and is a major character in the Cold Steel arc. Sara's past is a mystery, though one thing is for certain, she is very carefree today. She became an A-rank bracer before becoming an instructor at Thors Military Academy, known as the Purple Lightning. She eventually came to be an instructor, and has an interesting way to instruct the students. She is very lax when it comes to deadlines, and tends to go out on the town to get drunk...a lot. She makes quips a lot on the fact that she's single, and can be slightly seductive at times with her lines.

Sara has a medium-low voice, and mature at that. Her tone is a carefree one, at times having some serious moments. Her non-battle quotes involve emotions with happiness, persuading, and seriousness.