I'm so Good, How Could I Be a Murderer?

Another double knock... Once suspected, Qu Yuan helplessly looked at the policeman opposite. "Mr. Police, do you have any evidence? Why are you holding on to me? All the evidence points to my brother being the murderer. Even he admitted it, didn't he?" The policeman opposite just glanced at her, suppressed the anger in his heart, and said without a doubt "You did it on purpose." He deliberately hinted that he was the murderer, but refused to give any substantive evidence and kept them fooled. "Don't talk nonsense, I am a good citizen." Qu Yuan was not worried at all until the police found... How should she break the situation, is she the murderer, and what will be her ending? Demining There is no male protagonist, just friendship, and the female protagonist is not a traditional good person.