At Okagi Castle, Yuuki reveals to his childhood friend An that his family will be moving away. Promising to return in the future, Yuuki expresses his desire for them to date when they meet again. Fearing that their emotions may alter over time, An dashes away in anxiety but stumbles upon a mysterious portal at the castle's entrance. Venturing through, she suddenly finds herself 50 years ahead. In her bewilderment, An encounters Kibou and his helpful robot, Butler-kun. Serendipitously, Kibou's grandmother had advised him to assist any distressed girls in the park, leading him to offer his guidance to An. While exploring the city together, An observes that despite Okagi's modern transformations, the town still retains its timeless nostalgic allure.