Self-professed "home security guard" Mahiro Oyama has not left his home in years, secluding himself in his room playing erotic visual novels. This depraved lifestyle causes his prodigious sister, Mihari, to worry about his well-being. In hopes of solving this problem, she devises a plan to rehabilitate him back to normalcy. The first part of Mihari's plan is to concoct a medicine that changes her brother's biological constitution into a bona fide female, much to Mahiro's vehement dismay. Stuck in this predicament, Mahiro has no choice but to live out his life as a cute girl until the effect wears off—if it ever does.

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.

Akira Kiyose, a high schooler who loves to sing, gets recruited by a talent agency called sMiLea Production. Akira learns that the legendary idols "Anela," who shocked the world with their sudden retirement, are behind the agency developing talent. Together with Banri Naoe and Chihiro Isuzugawa, also recruited by the agency, they form an idol group as they chase their dream towards super stardom alongside other idol groups "LEGIT" and "JAXX/JAXX."

Arisugawa Academy's DJ unit Lyrical Lily is known for bringing smiles to people's faces through music. Thanks to their efforts, the local city hall requests them to perform monthly for a year as part of Operation Beckoning Cat, the town revitalization project. Unfortunately, given the long and demanding event, Lyrical Lily wonders if they can successfully meet the expectations placed on them. To better their chances, they decide to invite the DJ units that supported them during their first performance: Happy Around, Photo Maiden, Peaky P-key, Rondo, and Merm4id. Intrigued by the opportune event, the other units gladly accept Lyrical Lily's request. However, the project is extremely demanding. To attract visitors and new residents to the town, the energetic girls of the participating DJ units must give their best to create a memorable experience for their audiences.