Mitarai Yo is a career woman who works for a shoemaker. She finds her work rewarding and has successfully advanced in her career. But she keeps having her heart broken and her romantic life has not gone well lateIy. Ishida Ren works for a developer and is Yo’s best friend. As a former high school and university classmate, Ren is the only person she pours her heart out to, and he understands her best. On Yo’s 29th birthday, the friends place a wager with each other to see which of them can be married within the following year. If either fails to wed prior to her 30th birthday, the loser must pay the winner a congratulatory sum of 300,000 yen. Declaring it impossible for them to fall in love with one another, their wager, plus the advances of a junior of Ren’s at his company and Yo’s reunion with her ex-boyfriend, Mizusawa Ryusei, all lead to gradual changes in the relationship of these best friends. (Source: Jdrama Weblog)