Hoshino comes back to his childhood place. He goes in pursuit of a monkey taking his brothers hat and meets Ui. He kisses Ui by accident by falling on her and Hinata appears and thought Hoshino forces himself on Ui calling him a pervert. When the brothers reach the Yorozuyo inn they are welcomed by the owner and shows them their room. When Hoshino came to bathe he was accidentaly seen naked by Tsumugi Todo and the owner of the inn Senka Yorozuyo. In the morning they go to the school they transferred in and Tsumugi shows the brothers the way to their schools. When Hoshino enters the class, Hinata notices him and she was surpirsed to see him in their school

Hoshino gets shown around the school, makes new friends and gets shown around the town. The title comes from Hoshino saying "That's why it tasted like cheese" (Referring to Ui's muffins that she had for lunch) when Ui bought lots of cheese treats from a shop, explaining that she likes cheese. Ui takes Hoshino's comment the wrong way, thinking he was talking about the kiss.

Following an awkward morning and breakfast with Senka, Kazuma and Ayumu head to school with Daigo. As Ui and Ibuki catch up, Kazuma experiences an aura that he is being watched. Class breaks for lunch; on his way with Daigo to get food, Kazuma experiences another aura as a girl hides. Homeroom is let out; as Kazuma leaves with Daigo, he spots the girl and gives chase. Bumping into and startling Madoka instead, bodyslams him onto the floor. The next morning, shooed out of the inn, Kazuma rethinks the incident and decides to apologize to Madoka; finding her at the shrine. Making up, she inquires about him and Ui, brought to tears upon hearing they kissed. Watching this from atop a tree and upset at Madoka crying, the girl from earlier reveals herself to be Koyori Toudou, Tsumugi's other sister. Berating the poor boy with acorns, and to the defense of Madoka, Koyori pardons Kazuma and leaves. On their way from school the next day, Ui and Kazuma bump into Ayumu. With a moderate fever, Kazuma piggybacks him the rest of the way as Ui fantasizes about being carried. Back at the house, Ayumu asleep, Kazuma and Ui relax in his room. Senka drops by with Tea and Daifuku, of which Ui immediately begins to make a mess of herself eating. To his amusement, Kazuma laughs.

On his way to the bathroom, Daigo tosses his lunch to Kazuma, who stumbles backward into Hina Sakai, a third-year student, knocking both of them over. Apologetic, he picks up and returns her cellphone, complimenting the cuteness of the ornament dangling from it. Hina mistakes this as ridicule, snapping back and leaving. Back in class, Kazuma, Ui, Ibuki and Daigo sit to lunch discussing the upcoming sports festival, specifically the renown Hikonan Race, a form of triathlon. As participants in this event represent a business, Kazuma is informed by Senka upon his return that he will be entered on behalf of the inn. He heads out on a jog to prepare, finds Koyori up a tree in the park, and breaks her fall when she slips off. Reconciled, he accompanies her to Gengorou Yamakawa, an elderly friend and widower. The man talks of his late-wife, specifically his hospitalized grandson, Keita, awaiting an undisclosed surgery, making plans with Koyori to visit him. Back in her room, Hina makes the decision to apologize to Kazuma. Koyori and Gengorou surprise Keita the following day; in an effort to keep his spirits high, Koyori promises Keita to enter the Hikonan Race and place first if he will remain optimistic about the surgery. After a brief encounter with Hina, who does not apologize, Kazuma finds Madoka at the shrine; where she tells him more about the story of Futagoyama.

The school games are on and Ui, Hoshino, Hinata and friends are all participating. The title comes from the last event in the games, when they have to all do a series of random tasks in a race. First, they must each eat 30 bowls of red bean soup, then they must catch eels, then they must pick a card and dress up in the costume that matches (The wedding dress).

At school the next morning, Kazuma, Ibuki, Ui and Daigo, in preparation for finals, arrange a study group at the inn. After five and a half hours of studying, the group break to take baths and watch fireflies; it is revealed around this time that Hajime was married when Ui was very young and that it had a negative impact on her. Finishing dinner, the group turns in for the night, Kazuma bumping into Ui on his way back from the bathroom. The two sit outside and share a plate of onigiri as they discuss Futagoyama. Waking up to Ui missing, Madoka peers outside one of the room windows, rueful to see her and Kazuma standing together.

With finals over, everyone save for Ibuki and Ayumu plan a trip to Honchou, a nearby metropolis, to celebrate. When a bus is unavailable to accommodate the group for two hours, they detour to an arcade to pass time. Having stayed at school to practice, Ibuki finds it difficult to concentrate, Kazuma on her mind. The group assembles the following week to watch her participate in a nationwide target archery competition; despite making it to the finals, Ibuki is eliminated. Kazuma finds the distraught girl at the overlook, cheering her up.

Kazuma calls up each of the group the next morning, inviting them to visit the beach with him the following Wednesday. Everyone agrees, and the gang spends a fun and exciting day playing in the sand and in the water. Madoka takes the opportunity to ask Ui about her relationship with Kazuma, relieved to hear that she considers him more of an older brother than a love-interest. Finishing up their stay with a game of suikawari and volleyball, the group head out at sunset. On their walk back home together, Ui curiously asks Ibuki about her and Kazuma.

On his way back from a trip to Honchou, Kazuma finds Hina at the park alone and hungry. Buying the desolate girl food and drink, he sits with her as she describes a recent fight with her father that drove her to run away, left with nowhere to go. Against his better judgment, he discreetly takes her in. Senka discovers the hidden arrangement but agrees to house Hina in exchange for housekeeping. News of this reaches her father, and following a failed attempt to extradite his daughter, Kazuma is challenged to tug-of-war in her name. The battle is fierce and close, but thanks to no small measure of luck, Kazuma wins.

Returning to the shrine and thus absent from the event, Madoka is brought up to speed about the tug-of-war, sullenly mistaking it to be a proposal to Hina. Koyori, home from vacation, visits her upset friend to the apparent news, rushing to find Kazuma in the company of the others. Following a brief shock from everyone, Kazuma straightens out the story. Daigo is more than convinced that Madoka must like Kazuma, recruiting the help of the girls to orchestrate a date for them at an amusement park. The couple spend an enjoyable day there, so much that Madoka invites Kazuma on a picnic the next morning. As the two get settled by the stream, placing her windblown hat back onto her head, Kazuma realizes she is the girl from his childhood.

School back in session, Daigo reiterates his discontent to Kazuma about rejecting Madoka on their way to class. As Kazuma tries to explain otherwise, she happily catches up to them. Class out for the day, and walking home together, Ibuki neutrally warns Ui that unless she confesses to Kazuma soon, someone else might; including herself. That night, as both girls ponder the conversation, Ayumu calls Ui and asks if she will model for him the next day. That morning, acting on behalf of this, Senka shoos Kazuma out of the inn. Aimless and bored, he decides to visit the shopping district, bumping into Ibuki along the way. The two instead travel together to Honchou and spend the day playing arcade games, trying on clothes, dining, and singing karaoke. Back at the house, Ayumu takes a break and sits with Ui who is surprised to learn that the drawing is a gift for Kazuma, as he believes they're dating. As the day closes in, Ui bids her regards and walks home, upset. Sitting at the park, Ibuki happily thanks Kazuma for their time out, jokingly describing them as a couple and though serious, playfully asks him out. He sharply turns down the offer and leaves; though a minute or so into doing this, runs back to apologize. Fighting the urge to cry, Ibuki, heartwrenched, maintains her offer was a joke; returning home as rainclouds drench her. Back home, discontent with her behavior from her brother's marriage, Ui calls him to the surprise that his wife, Kuriko, is pregnant. Ibuki heads to the overlook early in the morning to vent about Kazuma. As she heads to school, Ui catches up, overjoyed that she is going to be an aunt.

Sitting with the boys at breakfast, Senka informs Kazuma that as the winner of The Hikonan Race, he is to play the Ogami[a] in the upcoming festival's Futagoyama ceremony. Though skeptical of the idea, he agrees. On his way to school, Daigo encourages him to use the opportunity to get with Tsumugi, the Megami,[b] and by extension, the prettiest girl in the entire town. Ibuki happily catches up to them as Ui bashfully approaches; a silence drawn between herself and Kazuma. Class over for the day, Ui and Kazuma sheepishly walk together to the shrine in practice for the ceremony. Having sensed something during dress rehearsal, Tsumugi sits with Ui to discuss her recent behavior around Kazuma; despite Ui's efforts to cover up and derail the topic, Tsumugi finds it to be nothing shorter than love. The day of the ceremony comes. As the girls prepare to get dressed, Tsumugi collapses and complains of abdominal pain, asking Ui to take her place as the Megami. Kazuma follows rehearsal, driven on a float to one end of a bridge above the iconic stream. In the distance in an identical manner, Ui is wheeled to the other side. Caught off guard and with nowhere to go, Kazuma gazes at her speechless as the town stares in awe. His emotions build to an unbearable level, and deviating from plan, shouts at the top of his lungs that he is in love with her. Following some persuasion from Ibuki, Ui reciprocates. An afterparty is held at the inn. In the back, Ibuki and Madoka come to terms with being rejected as Kazuma and Ui kiss under a constellation of a bridge.