[catwhowalks]

I have a theory that it is indeed Misora--but that she's totally not aware of it and has not memory of doing any such thing. When she's in her powered state, she remembers nothing afterwards and seems to instinctively protect people close to her. I would not at all be surprised if, after talking to Sento, Stalk figured out how to temporarily trigger such a state and use it to trick her into revealing the information. Stalk is really good at manipulating things like that and I would put nothing past him at this point.