Armin Arlert (アルミン・アルレルト Arumin Arureruto) is a main character in the Attack on Titan manga and anime series. He is the childhood friend of Eren Yeager and Mikasa Ackerman, often hanging out with them in his youth. He has a great fascination with the outside wall, reading all sorts of books about it. This fascination caused many people to pick on him and call him a heretic.
Armin is very intelligent, often able to think of a plan in most situations. Despite this, he has very poor self-esteem, as he relied on his friends alot and isn't very physically fit. He is very determined to prove his worth.