A family of four moves into a house. The second son, Satoshi, murmurs, "Doesn't this feel somehow nostalgic?" The daughter of the house, Tsugumi, loves Satoshi and continues to have a forbidden relationship with him. Despite this, she also provides sexual relief for the eldest son, Tomokazu. When her father finds out about her relationship with her two brothers, he pressures her into a physical relationship... A beautiful girl murmurs to the troubled Tsugumi, "I share your fate..." It seems as if some secret and causal relationships are lurking in this house.