I usually write fantasy and historical fiction, but for the sake of trying something different I want to experiment with a more modern setting. Here's a sketch of my current plot bunny: The male MC has a habit of murdering any people who've pissed him off in their sleep, but no one knows he's responsible. In the story's first act, he murders a co-worker who beat him in a workplace competition. When his wife notices he's very sleepy the next day, he confesses his crime to her. The wife is horrified but decides not to report her husband, a decision which she will regret... Here's the challenge: I need a reason for the wife not to report her husband's murder. Right now I'm thinking that she simply loves him too much (he is otherwise charming), but don't know if that would suffice as a believable motivation. Also, if my story had to be fitted into a specific genre, which would it be?