“If you promise to keep my secret and become my “food” from now on forever...” Ruri, a frail and social slave, is supported by her favorite character from the otome game “Vampire House”, Gilbert”. One morning, Ruri becomes cold after pushing herself too hard. - However, when she wakes up, the world of the game has expanded, and Gilbert is even there...!! Ruri has been reborn as Fiona, the daughter of Gilbert's fiancée! In order for her not to be killed by him, and in order to watch her push up close, Fiona's struggle begins! And before she knew it, her feelings turned into ``I want to save him, who was never rewarded.'' The story of the rebirth of a cursed vampire duke and a mob reincarnated daughter begins.