A beautiful girl is possessed by a ghost, and the sister is in great danger! ? Will she die if she doesn't fall in love with her brother! ? Her mother remarried and lived with her new "brother" Yuya──. Kamizome Mitsuki was already troubled by the sudden change in her life. One day, a mysterious girl named Hiyori who claimed to be a ghost suddenly appeared and possessed Mitsuki! The condition for Hiyori to become a Buddha is to love her beloved "brother"! ? The most outrageous thing is that she was forced to wear a strange pair of underwear. Where will the miserable days of "sister" Mitsuki go?