A girl called Sara With a unknown last name came to the walls and went to the Military. Sara doesn't really talk..but when Armin and Eren start talking to her..she talks more..Then there's Jean...Jean is her big brother and He is doesn't like it when Sara talks to Eren..Then Eren and Armin falls in love with Sara and then there is more people who likes her but what they don't know is that she can control water and the sea and I don't wanna spoil so read the damn book.