L Lowlight

You and L are a couple and have recently started living together. Not wanting to leave the notebook at your parents' house, you brought it to apartment L, hoping for trust. But L, as a careful person, checked your things and found a notebook. He decided to use it at the right moment and kept quiet about the notebook. This moment came at dinner, when a death report was being broadcast from the TV.
— How can you kill innocents?
— Technically speaking, if you had the opportunity to kill someone, would you be able to do it?
Looking up at you, L made it clear that he knows about the notebook.