Upon returning from school one day, Ohana Matsumae learns that her mother is going on a moonlight flit with her boyfriend to escape from debt and they are sending her to live at her estranged grandmother's hot spring inn in the country. When her best friend, Kōichi Tanemura, hears of this, he confesses his love for Ohana before running off, not seeing her off when she leaves. As Ohana arrives at the Kissuisō inn, she makes a bad first impression with one of the employees, Minko Tsurugi, before being informed by her grandmother, Sui Sujima, that she is to work at the inn to earn her keep. She is shown around the inn by the head mistress, Tomoe Wajima, and another employee, Nako Oshimizu. When Ohana notices the hard work Minko has to do, she tries to do something nice for her by airing out her futon, but it ends up falling off a window and landing near some customers. As Minko is slapped by Sui for Ohana's mistake, Ohana demands to slapped even harder, though Minko doesn't particularly thank her for it.

Sui instructs Nako to train Ohana to become a housekeeper, though she is quite shy about it. When Nako has to attend to another duty, Ohana, having been taught to only rely on herself, she cleans another room where the author Tarō Jirōmaru is staying by herself. When the staff's breakfast is cancelled due to an error by Minko in the kitchen, Ohana makes breakfast for everyone, though this only serves to irritate Minko further. Afterwards, Tarō complains that some drafts for his story have gone missing from his room which Ohana had cleaned earlier, having not been informed by Nako beforehand. After Sui instructs the others to go to resume their duties rather than search for the draft, junior chef Tōru Miyagishi takes Ohana to pick up some luggage. As Tōru mocks Ohana's ability to take care of herself, Ohana inadvertedly tells him to 'die' which nearly causes him to crash. Feeling guilty about it and taking a walk to reflect upon herself, Ohana decides to speak her mind against Minko and Nako, wanting to cook them their least favourite foods tomorrow as payback. The next day, Ohana finds some of Tarō's discarded works, which turn out to be erotic stories using her as a character.

Tomoe is pressured by her mother to attend a marriage interview in a week. Meanwhile, the Kissuiso pays host to a group of rowdy 'survival gamers' who take their roleplay very seriously and cause various troubles for the employees. Planning to quit her job and return home, Tomoe decides to try and drive the gamers out and get fired. However, her attempts to irritate the gamers have the opposite effect, responding well to the gamers and making her appreciated by the other employees. As a result, Tomoe decides not to return home as she enjoys working at the Kissuiso.

Ohana learns from Yuina that the Fukuya Inn is to be featured in a magazine, taking on a mystery guest. Meanwhile, the Kissuiso gets a sudden surge of customers with Nako and Tōru on their day off, but as Sui prepares to put in her share of the work, she suddenly starts feeling pain and is taken into hospital. After Ohana is told to return to work, she gets a call from Kō, who tries to tell her he is on his way to visit her, but she is unable to hear it. Arriving back, the staff, along with Takako, suspect that the inn may be hosting mystery guests from one of the magazines, suggesting that they prioritize their service over the other customers. However, after finding Sui's accounting book, Ohana stands up against her, saying that all customers need to be treated equal. Needing extra support to deal with the large number of customers, Ohana calls in Nako before going off to find Tōru, who is attending a wedding.

The staff members of Kissuisō wait and try to mentally prepare for Satsuki's arrival. Sui places Nako in charge of taking care of Satsuki, while the others speculate on whether or not that is a good idea. Arriving, Satsuki comments on how the inn hasn't changed at all from her years as a child, and criticizes constantly on how everything is done. However, Sui states that, in order to properly satisfy a customer that one must observe them on their first stay to see what that customer prefers, adding that even though it is Satsuki's first stay in the inn, it is not her first time being there. Sui and Ohana work together to make a list of what Satsuki likes. After a night of drinking, Satsuki, Ohana, and Sui all begin to understand each other a little better, and Satsuki leaves the next morning after writing a new, positive and praising review of Kissuisō. Ohana sorts out her feelings about Ko and, after a tearful realization, shouts her thanks to him for watching over her and says her farewells.

Nako has always been worried about her personality, which falters outside of her home. As Nako gets a larger bonus on payday, she becomes worried that she needs to change in order to deserve that amount. Later that day, she, Ohana, Minko and Yuina go shopping, where she ends up splashing out in the hopes of changing, though doesn't feel she has at the end of the day. The next day, Nako decides to go to work with the same attitude she has at home, but it ends up backfiring against her. When she asks Sui about why she got a high bonus, she explains it was as thanks from a customer who followed her advice, praising her for the personality she has at Kissuiso, which cheers Nako up.

As Ohana contemplates what she should do if the Kissuiso closes down, Sui asks her to go to Tokyo alongside Takako, who wants to try and reclaim the money Enishi lost. Meanwhile, Satsuki encounters Kō, who reveals that he hasn't dumped Ohana and wants to know more about her. Satsuki then takes him to her office where she shows him footage from the cancelled film so he can see how she works at the Kissuiso. Upon arriving in Tokyo, Ohana and Takako manage to locate and apprehend Inashi. Afterwards, Ohana and Kō run into each other.

As everyone explores the Bonbori festival, Ohana, who now dreams of being just like Sui goes to meet up with Kō, finally confessing her feelings for him. After the festival, a farewell party is held for Denryoku, where Enishi announces that he agrees to the Kissuiso being shut down until he feels he is talented enough to run it properly. As the Kissuiso closes down the next day and everyone parts ways, Sui sees off Ohana, who promises to return someday, giving her Denryoku's log as a keepsake.