Nao's husband, who has been married for two years, brings over a subordinate from work. The subordinate, who becomes a kiss maniac when drunk, gets drunk and kisses Nao right in front of her husband. Her husband is upset, but thinks it would be childish to get angry. She remains silent at the time. However, this incident is the start of a relationship between Nao and her subordinate, and eventually Nao becomes obsessed with the feel of her husband's subordinate's lips and begins to desire him herself.