The experiment (MHA X op experiment! Reader AU)

UA has gotten a new student who is really and I mean really mysterious. She is really mysterious and I mean really. She always seems cold and guarded against everybody. will they find out who this girl is? Will they get her to open up to them? Will she trust them enough to tell them about herself? What will they do once they find out her past? What will the think of her? Will they treat her any different? Read to find out more about reader and her past plus why she's like this.