It's New Year's Eve, and there's a countdown party at the luxury hotel, Babel. Kouta, a new hotel employee who's dissatisfied with his own status quo, finds his fate forever changed following an encounter with two mysterious guests: Ozaki and Naomi.

On New Year's Day, he bears witness to a world-changing event. And with The Babel as his stage, navigating a complex web of human relations, Kouta's mission begins!