In the year 2187, humanity has created a perfect future—no wars, no pollution, and a society focused on happiness. But for Yuto Takeda, a 25-year-old researcher of mundane history, things are about to get complicated. After a time-travel mishap, he accidentally brings Nanami, a feisty 21st-century girl, into his utopia…

Yuto’s job is to study the mundane details of humanity’s past—things like ancient breakfast menus, old social media trends, and 21st-century dating customs. It’s a simple and relatively uneventful life—until he accidentally stumbles upon an unregistered time rift and pulls Nanami, a spirited girl from the 21st century, into his perfect future. Now, Yuto is stuck hiding a sarcastic, time-displaced roommate who can’t stop questioning everything about his world.
As Yuto and Nanami try to figure out how to send her back, they uncover small cracks in their supposedly flawless society. Alongside his sarcastic AI assistant, Professor Chronos.