Naoya Mukai is having the time of his life after his childhood friend Saki Saki finally accepts one of his countless confessions. Ensuring that their relationship will stay strong, he spares no effort in showering affection to his now beloved girlfriend. However, one afternoon, another girl named Nagisa Minase suddenly confesses to Naoya following months of preparation. Even though he politely rejects her, Nagisa's irresistible charm and determination continue to attract Naoya. Wanting to fulfill both Saki and Nagisa's desires, Naoya ends up proposing a crazy idea—to date the two of them simultaneously, with both girls fully aware. This unprecedented state of affairs ultimately causes wacky and hilarious situations in whatever they do to keep their unusual relationship going.

When, after her sudden death, Rinko Hanasaki is reborn as Raeliana McMillan, she is not sure whether to curse her luck. Raeliana was a minor character in a novel Rinko read, and as the eldest daughter of a nouveau-riche baron, she led a carefree life until her unfortunate demise at the hands of her fiancé, Lord Francis Brooks. To avoid her destined fate, Raeliana is determined to end her engagement with Francis. However, when Francis refuses to break things off, Raeliana decides to seek help from someone of higher standing and approaches Duke Noah Wynknight—the novel's male protagonist. Using her knowledge of the plot, Raeliana captures the duke's interest by proposing a deal: she will not expose his secrets if Noah agrees to act as her fiancé. Little does she know that getting involved with a duke who only shows his true colors around her may lead to more than she bargained for.

With her late grandfather's inspiring words in mind, Chizuru Mizuhara teams up with her friend Kazuya Kinoshita to launch a crowdfunding campaign for an amateur film. The two hope that with the success of the project, Chizuru can honor her grandparents' wishes before she loses her grandmother as well. After their wild encounters with three girls—Kazuya's clingy trial girlfriend, Ruka Sarashina; their nosy new next-door neighbor, Mini Yaemori; and Chizuru's shy work friend, Sumi Sakurasawa—they all collaborate together to reach the campaign goal and begin production of the film. As their ambitious endeavor progresses, Chizuru and Kazuya grow closer and begin to struggle with their mutual feelings.

Kannazuki no Miko begins in the village of Mahoroba, where time passes slowly for both man and nature. Two students from the village's prestigious Ototachibana Academy might as well be night and day. Himeko is shy and unassertive, while Chikane is bold and elegant. Despite this, they love each other, and nothing can come between them, no matter how hard they try. On the two girls' shared birthday, a sinister voice corrupts one of their friends into attacking them, and just when it seemed grimmest, the lunar and solar priestess powers that lay dormant in the two girls awaken, dispelling the evil. That was only the first hurdle, however. The two must now fend off the countless others who would threaten their well-being—even the people closest to them!