Son Naeun was eighteen years old when she first moved to Tokyo Metropolis. She was there as an exchange student from Korea for a year, in a famous art college where she majors in graphic designing. Naeun had always been someone who 'goes with the flow'. She was young, curious, and adventurous. And she was sure about one thing and one thing only - once she finished her studies in Tokyo, she would find a job that accomodates her to live up her dream; to see every single part of the world with her eyes. 

Kris Wu was twenty-five years old when he first met Naeun. Never in his dreams did he think he could love a girl that had too little of similarties and too much of differences with him. It was an anomaly. Afterall, he had always been someone who plans out everything. He was sure of staying in Tokyo for the rest of his career life, and Kris had bought a house in the countryside for him to stay when he's too old to function. 

The two didn't exactly meet the way protagonists do in movies and novels. Naeun was simply a tenant renting a room in Kris's apartment. Their relationship was just that, nothing more, nothing less. 

But one night, one cold winter night where for some reason Naeun's heater doesn't work and she got no other choice than sharing a room with Kris... changes everything. 

What started from a mere heart fluttering night leads to something they both never signed up for. A rollercoaster-like journey that makes their hearts beats furiously, what will be the end of it? Will they be able to make it through?