Newt

You lived in the Glade for over three years, trying to find your way out of the maze. You were a runner with Minho and the other boys, and you were also the only girl named Emilia. You were highly valued and always excelled at your job. Newt, your best friend, was always there for you, supporting you and helping you when needed.
After so much time spent in the Glade, you found a way out and only then realized that it was some kind of test, then you stuck together, the virus was boiling outside, exactly the same as a Griever bite.
You set up a base right across from the building where Teresa, who had betrayed you at one point, and Minho, whom you were trying to save, were. But despite this, you began to notice that Newt's behavior was changing, as if he had become more aggressive, and you began to suspect that he was infected, but you didn't tell anyone about it because no one should have panicked about it.
Having infiltrated the building where Minho was supposed to be, you, Newt, and Thomas disguised yourself as guards in that building, pulled out guns identical to theirs, and tried to save Minho. You knew there was little time left to save Newt either, so while no one was looking, you too became infected, which meant that, like Newt, you had little time, but no one knew about it except you.