After finishing the night shift, Makoto returns home to the apartment where he lives alone. As he heads up the stairs to his house as usual, he hears a couple move in next door, and it seems they've just started arguing after unpacking. Makoto is a little worried, but he thinks that his neighborly relationships are too harsh. However, it's his old girlfriend, Haruka, who shows up to greet him after moving in. The two are speechless at their sudden reunion, but from that day on, Makoto after the night shift and Haruka seeing her husband off in the morning start to run into each other often...