Wataru visits his aunt's house nearby to run an errand. Usually her husband is around, but today Wataru finds himself alone with his aunt. He feels slightly nervous, noticing her behavior is unusually affectionate—she's touchy-feely and overly warm. Though Wataru senses something strange, he decides to leave once his task is done. Just as he's about to go, she suddenly asks, "Won't you come take a bath?" Surprised but intrigued, Wataru accepts. Once in the bathroom, she unexpectedly enters wearing seductive lingerie. Flustered and overwhelmed, Wataru gets caught up in the charged atmosphere as events take an intimate turn.