[DeepL Translation - needs review] Volume 1 Introduction: I died of exhaustion while playing a video game and was reincarnated as Cain, a character in an Otome game, and I was captivated by the overwhelming cuteness of my younger sister, Diana. However, I knew that if I continued to progress in the game world, my sister would face a spectacular bat's end where she would be raped in a remote area or killed by an assassin. I vowed, "I will make my sister happy in this world! I vowed to make my...
