Whilst shopping for some flowers in her local market, Tamako Kitashirakawa, the daughter of a mochi shop owner, encounters a peculiar talking bird named Dela Mochimazzi that decides to follow her home. As Tamako and her younger sister Anko go to the public baths later that evening, Dela has Tamako's childhood friend, Mochizō Ōji, take him to the baths as well. As New Year's Eve arrives, with Dela having put on weight after gaining an affection for mochi, Dela almost chokes on a mochi, prompting the neighbourhood to help him out, overlooking Tamako's birthday.

Anko becomes disappointed that she can't go a museum with her friends, including a boy from her class she likes, because the market is preparing for a festival. Luckily, her grandfather says she'll be able to go if she wakes up early and finishes up all her jobs. Meanwhile, Dela is cast as an ornament for the festival's shrine. As Anko prepares to go to the museum, the florist asks for her help in dressing up some children, foregoing the museum in favor of giving one of the girls her support. When the boys from her class arrives, Anko becomes embarrassed and shuts herself in the closet, although she eventually comes out when one of the boys brings her a souvenir from the museum.

Noting that not too many people come by the market during hot days, Tamako suggests they put on a haunted house to help cool people down. As Tamako, Midori and Kanna work on preparing the haunted house, Mamedai claims he saw some ghosts floating about at night, leading the shopkeepers to become paranoid, believing the market to be cursed. After a test run by Shirori and Dera, the haunted house starts gaining some attention whilst Shiori helps clear up some of the 'hauntings' the shopkeepers have been experiencing. The haunted house proves to be a huge success, drawing lots of customers to the market. At the wrap-up party, Kanna reveals she and Dera were behind the ghost sightings from before. As Dera falls over in shock, his eyes once again project a video from the foreign prince, informing everyone that someone named Choi is coming to the market.

Deciding his obesity needs to be addressed, Tamako, Choi and the others decide to put Dera on a mochi-free diet until he loses enough weight to fit into a birdhouse Kanna made. In order to keep watch over Dera to make sure noone feeds him, Choi goes to school with Tamako and the others, where she joins in on classes and helps Dera get some much needed exercise, before going to a used clothes store. As Dera shows up the next day with a curiously slim body, Kanna and Midori give Choi a sweater they made for her.

With the school cultural festival approaching, the Baton Club manage to get a key timeslot for the main stage. However, Midori struggles to come up with some choreography for their performance, finding herself unable to admit it to Tamako and the others. As Midori becomes more stressed, leading to her catching a fever, Shiori mentions to Tamako and Kanna about Midori's worries. The next day, Tamako and the others visit Midori after hearing about her fever, she admits that she had been unable to come up with any choreography and is overcome with guilt. After Dera cheers her up by performing an amusing dance, Tamako, Kanna and Shiori help Midori come up with choreography, managing to come up with something come the day of the festival. As Choi comes to the school to give the club her support, she notices a particular mark on Tamako's neck, later announcing to Tamako that she is destined to become her prince's bride.

As the whole shopping district takes an interest in Mechya, Tamako feels a little confused by everything, the empty shopping district begins to remind her of when her mother died. When asked by Dera about what she thinks of the whole bride business, Tamako talks about how much the district has meant to her over the years. Tamako rushes to turn down Mechya's proposal, only to learn that she isn't actually a candidate, as Choi has misunderstood things. After the girls see them off, Choi and Mechya head back to their home country, only to realise they've left Dera behind. Come New Year's, Dera attempts to head back home by hiding himself in a bouquet, only to wind up in a box Mochizō has ordered for Tamako's birthday and end up right back on Tamako's doorstep.