The Maze Runner-Group C

You already know the story of Groups A and B, but nobody remembers Group C...

Susan woke up in a metal Box, with no memory of who she was or what was happening. When the Box opened to reveal a group of girls, she is terrified and refuses to speak until one of the girls, a girl called Lily, tells her that she is in the Glade and would settle in better if she spoke to them. Gradually, they gain her trust, and she gains theirs. Especially the trust of a girl called Lucy who helps her settle.
Then, the next Greenie is a boy...