Secret Contract With The Black Duke

Story:

Read Secret Contract With The Black Duke / 黒公爵との秘めやかな契約 I was trapped by the man who killed my family and died in a freak accident while trying to escape… or so I thought, but I had actually returned to the past when my family was still alive. While searching for a way to protect my precious family, I encountered a demon. In exchange for granting my wish, the demon demanded my happy memories…?