Ken-tarou ends up spending his free days at his aunt and uncle's house. However, his uncle is away on a business trip, leaving him alone under the same roof with his aunt Sumire. Ken-tarou is constantly on edge with nervous anticipation. Unknowingly, or perhaps knowing his nephew's feelings, Sumire starts showing off her bare breasts every chance she gets. "Aunt, um, that..." Despite clearly teasing him, she never makes the first move, and her infuriatingly seductive play drives the innocent nephew's libido to its breaking point.
