Masamune, a third-year middle school student, lives in a town where all the exits have been sealed off due to a sudden explosion at a steel mill, causing time to stand still. Residents are forbidden from making any changes and spend their suffocating days in the hopes of returning to normalcy someday. One day, Masamune's mysterious classmate Mutsumi guides him to the fifth furnace of the steel mill, where they encounter a girl who cannot speak and resembles a wild wolf. The meeting between the two girls and Masamune disrupts the balance of the world, and the unstoppable "impulse of love" from boys and girls tired of their daily lives begins to destroy the world.

The Seto no Hanayome OVAs are new stand alone shorts with characters from the series and also two new ones. It is now the third year of school, San and Luna's dads are still being over protective. All the while Nagasumi has his hands full trying to keep everyone around him under control and rescuing damsels in distress.

In the near future when technology has significantly advanced, a famous AI TV fortune teller seemingly foresees high school student Asahi Kashiwagi's day with pinpoint accuracy. On his way to school, he encounters Aoi Izumisawa, Bai Mongfa, Karin Istel, Amelia Irving, and Ilya Ilyukhin. Despite meeting them for the first time, Asahi suddenly receives love confessions from all of them at the end of the same day, perfectly aligning with the fortune teller's prediction. As if that was not enough, Asahi soon learns that these five individuals are actually candidates to become his bride, and they have been invited by his father to live at Asahi's home. Left with no other choice, he reluctantly allows them to stay, resulting in a bawdy turn of events that brightens up his average high school life. However, as Asahi spends more time with them, forgotten memories gradually resurface. While uncovering the hidden truth, Asahi begins to believe that his fate with these potential partners might be more than just mere coincidence.

Known for her semblance to the Sadako character of The Ring series, Sawako Kuronuma is given the nickname "Sadako" and misunderstood to be frightening and malicious like her fictional counterpart, despite having a timid and sweet nature. Longing to make friends and live a normal life, Sawako is naturally drawn to the cheerful and friendly Shouta Kazehaya, the most popular boy in her class. From their first meeting, Sawako has admired Kazehaya's ability to be the center of attention and aspires to be like him. When Kazehaya organizes a test of courage for the entire class and encourages her to attend, Sawako sees this as an opportunity to get along with her classmates, starting with Ayane Yano and Chizuru Yoshida. Through each new encounter and emotion she experiences, Sawako believes that meeting Kazehaya has changed her for the better. Little does Sawako know, her presence has also changed Kazehaya.