It was the day, according to Ji-hun's dream, when they were supposed to first encounter each other. But they had encountered each other twice already, and there was one more thing. Rather, one could say that the major thing was that she might not feel the same way he did.
Even after trying at least ten thousand times, he was unable to forget about the incidents of the party, as well as what had happened after that: Ho-jin and Dae Jung had unknowingly taken him to the same place where he had seen the original collision happening.