Ymir (ユミル Yumiru?) is a graduate of the 104th Cadet Corps and member of the Scout Regiment. She also has the ability to transform into a Titan.
Ymir is a tall, slender young woman with intimidating golden eyes and middle parted hair often styled into a ponytail with long bangs at the sides framing her face. She has disheveled-looking brown hair held back with a red tie and usually wears the uniform of the Scout Regiment.
Ymir's Titan form is considerably smaller than most Titans, standing at 5 m and is the shortest intelligent Titan thus far. She has long arms, a large nose, rugged hair, small black eyes, small pointed ears, sharp fangs and claws allowing her to easily climb trees and tear into enemy flesh. Unlike others with the power of the Titans, the body is not well-proportioned because her head is too big. Unlike the Female Titan, her Titan form possesses no distinct, feminine features. Overall, it lacks the distinct similarity to her human form that the majority of other intelligent Titans show. Prior to eating Bertholdt Hoover and Reiner Braun's friend, her Titan form was noticeably thinner, and her rib cage was more pronounced, her teeth were also straight and not sharp. She is also shown to be capable of coherent speech in her Titan form.