During the sweltering summer vacation, I, who had just gotten my first girlfriend, was repeatedly drained dry by my aunt, who said, "This is sex practice!" while I was in the jacking position... (Tsubaki Kotoha ROE-528)

During a summer vacation marked by record-breaking heat, Ryosuke reports to his aunt, Kotoha, "I've got my first girlfriend." However, Kotoha, widowed and languishing in loneliness, is overwhelmed by the innocence of youth. Taking advantage of her family's absence, she seduces him with gentle words, saying, "This is practice for sex," but the guise of guidance crumbles, transforming into a frenzy of lust. On the final day, Kotoha restrains Ryosuke's hands and feet, indulging in the controlled ejaculation that drains his youthful vitality to its limit. During these seven immoral days, Ryosuke is utterly powerless against his aunt's venomous fangs…