I saw her again last night. The girl who once told me, "The most dangerous moment for humans is when they're just about to cross the line." The first time I heard her say that was in a dimly lit little room. She was very close, her voice so low it sounded like she was about to say something inappropriate for children— but instead, what she handed me was the accident report she had kept hidden for three years. That year, she was working on risk control model tuning at a data company.