When I was a child, my mother passed away due to illness. I vaguely remember her face, but it's a hazy memory. My father ran a company and we lived a luxurious life, but he was never home and I felt lonely. Then, six months ago, my father brought home Kumi. I felt that she looked somewhat like my mother, but she is not my real mother. Kumi treats me like her real son, but I somehow dislike her kindness. I didn't know why, but I finally realized. I was aware of Kumi as a member of the opposite sex.