The story is set in Hiroshima Prefecture's Onomichi City, where a high school student Nashiko Jippensha was kicked out of her house. Without a place to play with her friends, she learns that the mahjong parlor that her father used to run is now vacant. She fixes the mahjong parlor and turns it into a place where she and her friends can have fun, cook, have tea, and sometimes play mahjong.
One day, Nashiko Jippensha is kicked out of the house by her mother for making too much noise in her room. Having lost her place to party freely, Nashiko receives a call from her father telling her that she can use the old mahjong hall he used to run as she pleases in exchange for cleaning the place up. She immediately starts cleaning and then, a mysterious spirit appears from the store's mahjong tiles...?!
Riche finds Nashiko at the mahjong club, as she promised, and manages to convince her to let her join the group of friends. She also meets Pai, Izumi and Chombo and, around the mahjong table, a new friendship is created.
Now that the four friends know that the stove works, the next step is obvious: prepare a good dish! On the menu, a delicious curry accompanied by sashimi and ice cream for dessert. But before that, they start putting the old mahjong club in order.
Nashiko finds herself without internet on her cell phone after using up all her mobile data. So, she contacts her father asking for Wi-Fi to be installed in the store. With the Wi-Fi working, on Riche's recommendation, the girls decide to play mahjong online.
Riche defeated a strong opponent she met in an online mahjong game. While they were in a celebratory mood, their opponent in question, Emi Haneru, arrives. Immediately upon arriving, Nashiko is initially impressed to see her requesting a rematch with Riche. However, after hearing the words of Riche and her friends, she is inspired. Later, to deepen their friendship with the girl, the group begins a certain strategy...
Mahjong fans organize a one-night stay at an inn in Onomichi to... play mahjong. They also take the opportunity to visit tourist sites in the city that they normally don't have the opportunity to see. Haneru only hopes for one thing: to finally confront Riche and get revenge.
August 1st is "Mahjong Day". On this day, Pai celebrates her birthday, so Nashiko throws a birthday party for her on the beach. The group enjoys a unique birthday party, eating birthday cake on the beach in the middle of the day and playing in the sea. Later, as the party approaches its final stage, Nashiko and the others decide to give Pai a gift. However, right away, Riche presents her with something too expensive to be a gift...
Nashiko's mother invites her to help produce 3,000 paper lamps for the festival of lights, but with only 4 days available she will have to resort to the indispensable help of her friends.
The Becher Festival is a festival where parishioners dressed as demons chase children. One day, as the festival, which represents Onomichi City, draws near, Nashiko and Riche suggest that everyone go around the festival together. However, when Izumi hears this, she collapses. Worried by Nashiko and her friends, Izumi reveals that she was chased by a parishioner as a child and has been traumatized by demons ever since. So, Nashiko and her friends impose a certain training on Izumi in order to help her overcome her demon fears...
On December 25th, Nashiko and her friends decide to hold a Christmas party at the former mahjong parlor. On the day of the party, the table is filled with dishes they've all prepared, and everyone enjoys a special mealtime for just one night. Afterward, when they're full, they take a break and play mahjong. Suddenly, during the game, Nashiko, Pai, and Izumi all smile fearlessly. Seeing this, Tobi suspects Nashiko and her friends of cheating, but...
On the night of New Year's Eve, Nashiko and her friends gather to visit the shrine for the first time in the new year. After saying their prayers for the new year, the five of them eat soba noodles, draw fortune slips, and have a fun time early in the new year. Two days later, on January 3rd, Nashiko and her friends gather at the former mahjong parlor for their first game of mahjong. They start the game while munching on ozoni made by Nashiko and other dishes that everyone brought. Who will be the first to win in the new year...?
Nashiko and her friends are upset when Janta-kun, the electric mahjong table they've been using for years, breaks down. They try to repair it themselves, but it's too much for an amateur to fix, so they give up. After that, the frequency with which all five of them get together at the former mahjong parlor decreases, and naturally the time they spend playing mahjong also becomes shorter. Nashiko feels a bit lonely and sad about this situation. The other four feel the same way, but they are unable to change the situation and time just passes by...
