At the age of 29, Yo Mitarai is a successful career-woman at a shoe-making company but not that successful in her love life. Yo's high-school classmate Ren Ishida is working for a developer corporation and becomes her most close friend. After dinner celebrating Yo's 29th birthday, they had a bet: whoever gets married before the age of 31 would give the other US$3,000 as a cash gift.

Yo started using dating-app but always ended up with meeting the wrong dates. Yo's friend recommended a temple that can bring more luck in the love life and she went together with Ren. Yo had a great time there, visiting wedding ceremony venues and trying on wedding dresses. However, she also learned about that Ren's junior colleague Maki Kono is trying to ask him out.

Yo sets her sights on her new co-worker Yu; Ren goes out with the junior that's been crushing on him.

Yo was attracted to Yu, who turned out to be quite a considerate and hard-working young man. One-time Yo went out eating with Ren and Maki. She became jealous seeing how gentle and sweet Maki was to Ren and called Yu out to compete. On the other hand, Ren surrendered to Maki and agreed to be her boyfriend as "try-out. Without early notice, Yo was asked to go on a business trip with Yu to Nagoya.

Maki knew that Yo and Ren planned to go camping and decided to join. Yo found about that Ren and Maki were dating, shocked that Ren couldn't tell her himself. While Yo became unable to enjoy this camp anymore with Maki's jealousy on site, Maki was unhappy with Yo being too closed with Ren.