Ryouichi is a teenage boy who frequently visits his friend Yuu's house to play video games. During one gaming session, Yuu's married aunt, Yui, is present and joins them. While engrossed in the game, Ryouichi grows distracted when Yui initiates unsolicited physical contact with him, an action unnoticed by Yuu who remains facing away. Initially nervous about the transgression and fearful of Yuu discovering it, Ryouichi's reservations crumble quickly due to Yui's physical attractiveness, overriding concerns about their age difference and her marital status. The encounter intensifies after Yui engineers privacy by sending Yuu away from the residence.