Duker Stories

I was reincarnated as Nicholas Saltzman. The villain Duke who tries to seperate the heroine from the capture targets and bullies her only to get killed by the main protagonist in the end. Now that I have been reincarnated I have no interest in the heroine or the capture targets. I'm going to spend my time devoting myself to the duchy and become a good duke. But, something is not right. Why is the heroine always around me and why are the capture targets fighting with the heroine FOR ME!!!