The main character - a high school student Mitsuki Kanzaki, whose mother-razvedenka marries for the second time, a man who has a son a little older Mitsuki named Yuuya.After some time, the new stepfather Mitsuki sent to work abroad, and the wife follows him, leaving the farm stepbrother and stepsister. Mitsuki does not experience any feelings for Yuue sister, a mother feels abandoned and generally withdraws into himself. But one day heroine inhabits a ghost of a girl named Hiёri and Kotobuki,directly in the body of Mitsuki, she tries to seduce her brother. It turns out that Hiёri can not itself get to the gates of paradise and find peace. She needs to Mitsuki, which Hiёri wears a special belt, causing various "sexual response" from Yuui (eg, as a result of dating, kissing, etc.). Each time such a reaction occurs,belt "filled" and Hiёri can take another step on the bridge that leads to the gates of paradise. So now, to get rid of the annoying ghost Mitsuki to seduce his brother, even consolidated.