You were O-71 all along. The last incident you were involved in got Dr. Vasquez's sister killed. As revenge, he continually erases your memory and tortures you by pretending to be O-71 and trying to get information out of you so he can control you. But it turns out, your lie-detecting powers are involuntary. When someone tells you a lie, you can take over their body and see, hear, and feel everything they do. Dr. Vasquez has a clock in his room that drives you crazy (because you can hear everything he hears), so instead of leaving him alone, you force him to shoot himself.