Mikasa Ackerman is a fictional character in the Attack on Titan franchise. She is Eren Yeager's adopted sister. She is a quiet and withdrawn girl and maintains a stoic expression, except when Eren is in danger. When Mikasa's parents were killed by slave traders, she went into shock until Eren saves her and motivates her to fight back. As a result, she is very protective of Eren, and follows him wherever she can in joining the military and its related divisions and squads. She is the last-known person of Asian descent residing in the Walls. She graduates at the top of the cadet class, and is regarded by officers as an unprecedented genius and prodigy, easily worth a hundred men in battle. In the author's blog, Isayama notes that her name comes from the Mikasa, a battleship from the Imperial Japanese Navy.
Mikasa is voiced by Yui Ishikawa in the Japanese dub. In the English dub, her surname is spelled Ackermann, and she is voiced by Trina Nishimura. In the live-action film, she is portrayed by Kiko Mizuhara. Ishikasa says that Mikasa cares mainly about Eren, and keeps a distance from the rest of the world. She says that "While she might seem like a character with so few emotional levels, there are actually many feelings that swirl around her heart." More: en.wikipedia.org.