令小新万万想不到的是，进入了游乐园的爸爸妈妈都不在理会其他事情，只是一直沉醉在以往的时光里。城里的大人们都进去了，只剩下了小孩子！这到底是谁的阴谋，小新他们能否粉碎这阴谋？
在一个普通的小镇上，生活在一个五口之家的普通小学生高池直也（田村由里配音）、朋友铃木和村（清水爱配音）和伊丽莎·巴恩斯（奈宫理惠配音）过着无忧无虑的生活。这一天，他们偶然发现了一只类似水貂的动物，Yuno Skleia（由水桥香织饰演）。
Elya, 20, is a student and a future ecologist. One day, Matvey, the head of a construction company, came to her university to discuss the development plan for an old forest park. Elya did not hesitate to crush his project. Matvey is very interested in girls' confidence, And used his usual influence method - he just tried to ; purchase She, but Elya doesn't need a sponsor. Then, Matvey was surprised by her indestructibility and placed a bet on Elya: romantic seven days according to his rules. If the girl still decides to leave after that, he will refuse to build a skyscraper in the forest park. When Matvey really paused design work, she agreed. Elya thinks she's a bit like the movie 'Beautiful Woman' The female protagonist in, but it turns out that Matvey is not the person she imagined.
