Hajime works at a local post office, always a step ahead of everyone else—waking up just a second before his alarm rings. Reika, one of his regular customers, is the opposite: always a second behind. But one morning, the day after Valentine's Day, Hajime wakes up with no memory of the previous day. Reika, however, holds the key to unlocking the mystery behind his memory loss. As their paths cross, she reveals clues that may explain what happened -and perhaps, why. As the story shifts into a fantastical dimension, this romantic comedy weaves together sweet and poignant moments that make for a charming and heartwarming two-hour journey.