Natsunoko Mamiya is 28 and single. Since her office is full of guys, the only place where she can find comfort is the quiet smoking area at the back of the building. One day, she meets the new employee Hisaya Takao there, who asks, "Can I get a light?" Just as she's about to lend him her lighter, she looks up, and his cigarette tip touches hers in a cigarette kiss. From that day on, the two start spending time alone in the smoking area and quickly develop a close relationship. Even though he's younger than her, and her junior in the company, Natsunoko can't ignore her feelings… They light up and flicker inside her like a cigarette…