Kumiko leaves boondocks to attend college, where she meets sophomore education major Kenichi. When they start dating, they discover a problem.

After two years together, Kenichi applies for a job in Yamanashi. After some fruitless research, Kumiko later finds a ray of hope for their issues.

Now happily married, Kumiko and Kenichi are both teachers. After four years, Kumiko is moved to a new school and assigned a supposedly difficult class.

Following her discovery about Kenichi's activities, Kumiko struggles in her job at school. Problem child Miyuki quickly senses her weakness.

Kumiko begins discussing her problems on a supportive online forum, but when she meets one of the commenters, he turns out to be a man.

Kenichi and Kumiko are living parallel lives, separately pursuing physical gratification. His bank balance shrinks as she falls deeper into despair.

He's noticed Kumiko's increasing unhappiness, but even as he wonders where things went wrong, Kenichi finds himself unable to do anything about it.

Kenichi raises the possibility of using other methods of getting pregnant, but when Kumiko reveals her past sexual experiences, he walks out.

After seeing a specialist, Kumiko and Kenichi decide not to have children. When she tells her parents, they demand to speak to her in-laws.