記録的な猛暑が続く夏休み、叔母の琴葉に「初めて彼女ができた」と報告した亮介。しかし夫に先立たれ孤独に喘いでいた琴葉は、その初々しさに理性を失う 。家族の目を盗み「SEXの練習よ」と優しく誘惑する彼女だが、指導の名目は次第に剥がれ落ち、狂おしい肉欲へと変貌 。最終日、琴葉は亮介の手足を拘束し、その絶倫な若さを限界まで搾り取る射精管理に耽っていく 。背徳の七日間、叔母の毒牙に亮介は抗う術もなかった…。
During a summer vacation marked by record-breaking heatwaves, Ryosuke tells his aunt Kotoha that he has his first girlfriend. However, Kotoha, who has been suffering from loneliness since her husband's death, loses her reason at his innocence. Stealing glances from her family, she gently seduces him, saying, "It's just practice for sex," but the pretense of instruction gradually falls away, transforming into a frenzied lust. On the final day, Kotoha restrains Ryosuke's hands and feet and indulges in ejaculation control, squeezing out his youthful virility to its limits. For seven days of depravity, Ryosuke has no way to resist his aunt's venomous fangs…

– JavGG.net