Just like me! (Armin x reader)

(Y/n) Yeager was Eren's adopted sister. She carries her futon around with her everywhere. Without it she gets sick easily. When she meets Eren's friend Armin she finds that they have a lot of things in common. When Armin starts to come to school with Eren, Mikasa, and (Y/n); she realizes that she likes Armin. Does he...