Episode Summary: Today Haruka gets a well deserved break from school, and stays home while Kana and Chiaki head off for another day at their school. Haruka starts out her fresh day off by getting some chores out of the way, but has nothing interesting to do after that. As usual, Kana is spacing out in school, and thinks of how Haruka must be enjoying a delectable cup of tea. Since Haruka has nothing planned, she decides to cure boredom with working; so she cleans up the kitchen until it is squeaky clean. Chiaki is thinking of Haruka, as usual, and wishes her a good, relaxing day. Back at home with all the chores completely done, Haruka decides to read some books to pass the time. Back at Kana’s class, she is counting on a nice sweet cake when she returns home, and Haruka seems to have some kind of mental link, for she makes exactly a nice sweet cake.
This cake seems to have came from Heaven, a godly delectable cake, and is calling out to Haruka, “Eat me!” Haruka does say that she didn’t have any lunch, and eats the entire cake! As school ends, Kana is starving, and she returns home to find that Haruka has single-handedly slayed her precious cake! Kana explodes on Haruka, inquiring upon where her share of the cake is; all the while, Chiaki is thinking that she must protect Haruka’s day off. To do so, Chiaki tells Kana to stop embarrassing Haruka, she was shaving off her beard. The next day Kana is awaken to the weight of Chiaki upon her back, that is Chiaki’s way of getting Kana’s lazy butt out of bed. To get revenge, Kana vows to return the favor the next day; so, extremely early in the morning, Kana wakes up Chiaki to “talk into the night”.
Kana asks Chiaki why she believes so passionately that Kana is a complete idiot, and Chiaki responds that there are hundreds upon thousands of ways to describe what kind of idiot she is. As the hours pass by, Chiaki explains how Kana is an idiot until Kana decides to get something to drink, getting soda for Chiaki and orange juice for herself. With the extra caffeine and vitamins from the drinks, they pass out later that morning only to be awaken by Haruka, who states that they will not be receiving an afternoon snack. That next weekend, Chiaki is bent on revenge, so she enters Kana’s room and gets her into the living room in order to bestow upon her a ten thousand word report on how stupid Kana is; due to the lack of sleep, Kana has come down with the cold and is forced to stay in bed. When Chiaki returns home from school, she checks up on her poor sister, who is seeing a bus that says it is leaving for the underworld. Chiaki spends the entire day taking care of Kana, and confesses her sins against Kana; Chiaki tells Kana that she ate her cake the other week, and Kana responds that she ate Chiaki’s cake the other day. Chiaki responds with a knuckle sandwich.
Chiaki is taking care of her that night, Kana is half delirious, who states that she will get her back when she finally recovers. Just when Kana and Chiaki are talking heart-to-heart, Kana says that Chiaki should go watch T.V.; Chiaki states that it is much more entertaining seeing Kana all pitiful, which gets Kana all pumped up and miraculously cured. Alas, the cold has finally lifted from Kana, but has moved to Chiaki. Now the shoe is on the other foot, and Kana gets to treat Chiaki, and starts by trying to force-feed Chiaki an entire apple. After everyone is all in tip-top-shape, the girls sit down to have a nice, peaceful dinner; but what ho, Chiaki will not eat her vegetables! After dinner, Haruka goes to pick up everyone’s clothes from the cleaners; and to have a little fun, the girls try on each other’s school uniforms. While trying on Kana’s uniform, Haruka states that “it”, meaning breasts, barely fits.
This gets Chiaki envious of Kana and Haruka’s breast sizes, and she is next seen eating three types of vegetables in an attempt in increasing her size. The next day, Kana is yearning for some cheese lemon custard chiffon pie, but Haruka would not make it for her because the family has been eating a lot of sweets lately. In order to get some pie, Kana gets Chiaki to make one by telling her that Haruka wanted some; Chiaki states that making a pie is too difficult for their skill levels, and Kana responds that it isn’t the outcome, it is the thought that Haruka would want. With that statement, Chiaki says that that is the only intelligent thing that Kana has ever uttered in her meager life. When Chiaki is done with the cake, she brings it out into the living room to show Kana the final result, then returns to the kitchen to clean up. Later, when Haruka returns home, Chiaki says that she made the lemon custard chiffon pie that she wanted to eat; Haruka looks puzzled, and when she enters the living room, she discovers that Kana ate the entire thing.
Upon seeing the overwhelming evidence that Kana ate the cake that she made so hard to make, Chiaki is outraged, and shows vents her anger. Haruka states that it is fine, and that she appreciates the effort that they put into the cake. At that, Kana bursts into tears, and they come to an agreement to make another together. Thus ending Minami-Ke 09 “The Three Sister’s Weather”.