15 years have gone by since Mikuriya and Kusaka eloped at 17 after their parents refused to accept their relationship. Suddenly, Kusaka says he wants to break up with Mikuriya. The only reason Kusaka will give is that Mikuriya broke his promise, but if Mikuriya is able to remember the promise and beg for forgiveness, he'll rescind the breakup.
The rabbits' town is directly between the warring fox and raccoon territories, causing them to be dragged into their turf wars constantly. The foxes offer to protect the rabbit in exchange for the rabbits sending a bride for the head fox's son, Shirou. With no girls of marriageable age, rabbit Rikka goes to talk with them. Only for Shirou to fall in love with him at first sight.
After seeing how happy his parents were with his sister's wedding, Sakura, a secret, gay otomen, decides to get married. When he arrives at the matchmaking office, the counselor, Yuusuke, immediately realizes that Sakura is gay and informs him they can only match him with a woman. Shocked at being found out, Sakura leaves the store, only to be chased down by Yuusuke and his senpai trying to apologize. However, that's when Sakura recognizes Yuusuke as the elementary schooler he used to play with.
In college Nana was known as The Prince of Good Fortune because there was a jinx that any woman who slept with him would come across extraordinary opportunities. Using that jinx as an excuse, Kyouya asks Nana to sleep with him before dropping out. However, they are reunited when Nana come to temporarily help at Kyouya's job, wedding venue White Bell, in order to prepare for a mock wedding ceremony.
Childhood friends Chiasa and Kazuma have been dating for 8 years. When they're reunited with their childhood friend Tomoe, she is heavily pregnant and doesn't know who the father is, so the couple agrees to help her while she's pregnant. But, a year after the baby, Ayumi is born, Tomoe suddenly ask the to take care of her. The two begin their life as parents.
Ch. 5: At his female coworker's wedding, Kazuomi falls in love at first sight with the angel-like groom, Reiji. But after meeting him, he finds out the marriage is a sham and Reiji's actually gay
Ito and Nishi meet when they run into each other while individually playing the White Line Game on the way home from school and they must find a way around the other. The two continue this pattern everyday, until Ito starts avoiding Nishi after Itou suddenly kissed him, but not wanting to be apart Nishi finds him and the two begin the game again as a pair. But, as they get older, Itou's over-seriousness and Nishi's carefree nature begin to clash and their line starts to divide.
Ch.3: After his friend's wedding, Mizuno decided to switch jobs and become a wedding planner. Now, Mizuno's boss is Asumi, the motivation behind his change
Ch.1-2.5: At 6, Takara's peaceful days were destroyed by Kyousuke. 20 years later, despite constantly fighting, they ended up getting married. Now, Takara's stuck with Kyousuke's pride, misanthropy, and helpless love for him forever
Ch.1-2,5.5: When wedding planner Aizawa discovers his client Ichinose's fiance is committing marriage fraud, he offers a one night stand to comfort the heartbroken Ichinose. Afterward, Ichinose begins relentlessly pursuing Aizawa, even though Aizawa has no interest in being in a relationship
Nichijou Climax