In a futuristic society, Japan has implemented a complex system referred to as The Red Threads of Science to encourage successful marriages and combat increasingly low birthrates. Based on a compatibility calculation, young people at the age of 16 are assigned marriage partners by the government, with severe repercussions awaiting those who disobey the arrangement. For Yukari Nejima, a teen that considers himself average in every way, this system might be his best shot at living a fulfilling life. However, spurred by his infatuation for his classmate and long-time crush, Misaki Takasaki, Yukari defies the system and confesses his love. After some initial reluctance, Misaki reciprocates his feelings in a moment of passion. Unfortunately, before the two can further their relationship, Yukari receives his marriage notice. He is then thrown into a confusing web of love and lies when his less-than-thrilled assigned partner, Ririna Sanada, becomes fascinated with his illicit romance.

Humans have designed countless worlds—each one born from the unique imagination of its creator. Souta Mizushino is a high school student who aspires to be such a creator by writing and illustrating his own light novel. One day, while watching anime for inspiration, he is briefly transported into a fierce fight scene. When he returns to the real world, he realizes something is amiss: the anime's headstrong heroine, Selesia Yupitilia, has somehow returned with him. Before long, other fictional characters appear in the world, carrying the hopes and scars of their home. A princely knight, a magical girl, a ruthless brawler, and many others now crowd the streets of Japan. However, the most mysterious one is a woman in full military regalia, dubbed Gunpuku no Himegimi, who knows far more than she should about the creators' world. Despite this, no one knows her true name or the world she is from. Meanwhile, Souta and Selesia work together with Meteora Österreich, a calm and composed librarian NPC, to uncover the meaning behind these unnatural events. With powerful forces at play, the once clear line between reality and imagination continues to blur, leading to a fateful meeting between creators and those they created.

After finally completing the first route of his visual novel, Blessing Software's producer Tomoya Aki is optimistic about the future of his team and achieving their goal of creating the best game of the season. However, they still have a long way to go. For one, Megumi Katou still has an incredibly flat personality and is unable to fit the role of Tomoya's ideal heroine. The other members of Blessing Software, Eriri Spencer Sawamura, Utaha Kasumigaoka, and Michiru Hyoudou, often forget she is even there due to her lack of presence and character. Throughout the development of their game, Blessing Software learns the struggles of working in an industry where deadlines must be met and edits are made constantly, and the hardships of working in a group setting.

Though they couldn't be any more different, love has managed to blossom between Hajime Tsunashi, a hardcore otaku who shuts himself in at home while making a living off his blog, and his wife Kaoru—a hard-working office lady who, in contrast, is fairly ordinary, albeit somewhat of a crazy drunk. As this unlikely couple discovers, love is much more than just a first kiss or a wedding; the years that come afterward in the journey of marriage brings with it many joys as well as challenges. Whether due to their quirky personalities or the peculiar people surrounding them, Hajime and Kaoru find themselves caught up in a variety of baffling and ridiculous antics. But despite the struggles they face, the love that ties them together spurs them to move forward and strive to become better people in order to bring their partner happiness.