Mitsuki, who lives in a rural town, has a regular summer vacation where she works part-time at her uncle's inn. After finishing cleaning today, she relaxes in the bath. However, her uncle watches her with a lewd look. "She's starting to resemble her mother..." says her uncle, recalling her mother, whom he once had feelings for. The next day, her uncle calls Mitsuki over to clean the storehouse, where he ties her up in the dark and rapes her as he pleases. A summer vacation of hellish training begins...