Yukako (Megumi Kato) and Shigehisa (Hiroyuki Sato) are co-workers who are involved in a relationship. Yukako suspects that Shigehisa may be cheating on her. Noboru (Kosuke Takagi) is in a relationship with part-timer Saeko (Momoko Maeda). They also work for the same company as Yukako and Shigehisa. One day, Yukako faints in a subway station and Noboru comes to her aid. Noboru also confides to Yukako that he suspects his girlfriend Saeko is sleeping with Yukako's boyfriend Shigehisa. An opportunity then arises for all four people to gather in a small room...