What began as a casual Twitter conversation between two long-time friends who for years talked about writing a book together – Valynne Maetani and Courtney Alameda – has become a hot property that recently was sold to HarperCollins in a two-book, six-figure deal after an auction earlier this year in which four major publishers participated. The final contract was signed in June.

Seven Dead Gods, the YA novel co-written by Maetani and Alameda, who have both been represented by John Cusick (now with Folio Literary Management/Folio Jr.) since 2012, is scheduled to publish in winter 2018. While Cusick described Seven Dead Gods as a combination of “An Ember in the Ashes and Daughter of Smoke and Bone meets Akira Kurosawa,” Alexandra Cooper, the HarperCollins editor who acquired it, used more cinematic terms: “Mean Girls meets Scott Pilgrim vs. the World.”

According to the two co-authors, it’s simply the inevitable culmination of their mutual passion for horror, anime, comic book culture, and Kurosawa’s classic Japanese epic movies. In Seven Dead Gods, which is set in modern-day Japan, 17-year-old Kira, who is the victim of bullying at her school, finds solace working in her grandfather’s Shinto shrine. After realizing that she can see and commune with demons, Kira – with her younger sister in tow – partners with seven “death gods,” or “Shinigami” in Japanese, to save Kyoto from destruction.

Even before she knew what Seven Dead Gods was about, Cooper said, she was excited about reading the 50-page sample that Cusick sent her. “The prospect of working with both Courtney Alameda and Valynne Maetani, two talented and dynamic writers, got me immediately interested,” Cooper recalled. “Then, when I read the [partial] manuscript, I was bowled over. It was like nothing I’d ever read. [It] is hugely inventive and genre-bending with whip-smart humor and nonstop, outsize action. I feel like an extremely fortunate editor to get to be working on this book.”

In the initial tweet on January 16, 2015, which came from Alameda, she suggested that the two write a YA novel together that would be reminiscent of Seven Samurai, but “with a supernatural twist.” Perhaps, she added, “with Shinigami who defend a village against some sort of demon?” Maetani tweeted in response, “Awesome! How bloody can we make it?” When Cusick read their tweets, he recalled, he “hoped that they were not kidding around” and “immediately” contacted his clients, “begging them to put this incredibly original idea on paper.” Cusick, who has been a literary agent for almost a decade, and joined Folio last July, told PW that he always has been “drawn to projects that are totally different.”

Both Maetani and Alameda had their debut YA novels published in 2015: Maetani’s Ink and Ashes, the first in a trilogy, from Tu Books, and Alameda’s Shutter, from Feiwel and Friends. Both books received glowing reviews.

“I’m delighted,” Cusick wrote in his pitch to acquisitions editors, “to be able to share a thrilling novel with a non-Caucasian cast, co-authored by a Japanese American” that is a ‘blending [of] Japanese folklore, action, and romance.” He added in a recent phone interview that the two authors are “incredible perfectionists when it comes to their world-building,” and the completed chapters are “really strong and exciting.”

Reflecting upon her collaboration with Maetani, Alameda noted, “I don’t know why more writers don’t collaborate. Not only do you produce a better book – one born of two hearts and two minds – but there’s a certain sort of glee in finishing a chapter by dropping your co-writer into a plot mire, and then running like hell in the other direction.”