"What's a happy marriage?" Kaoru Kirishima, 29 years old, single. Dreaming of becoming a novelist, she dedicates herself to her writing activities alongside her work, but then, she finds out that the theme of her novel is "Happy Marriage." She finds marriage unattractive. It's the most distant topic she could think of, and she's been worried about it for days. In the midst of this, she happens to meet a man named Moroboshi who desperately wants to get married. They become close friends as they talk about their views on marriage. However, Kaoru's thoughts on marriage were painful and sad...