Keitaro and Naru are alone at Hinata House. They are in the hallway practicing their kissing, unfortunately Keitaro still has not gotten any better. He accidentally steps on Naru's foot, and she yells at him. Later, Keitaro is by himself wondering exactly where he and Naru are at in their relationship. Naru is in her room wondering the same thing, when Kitsune calls. She's extending her trip, which means Keitaro and Naru will be alone for quite a while. Keitaro points out that Tama-chan is still there, but Tama-chan subsequently leaves also. Trying to figure out what to do, Keitaro and Naru decide to go into town for lunch.
On the bus ride back home, they discuss whether or not it's proper to close one's eyes when kissing. At Hinata House, Naru catches Keitaro looking at her, and she teases him about being a pervert. They chase each other, until both are exhausted. They relax on the deck, and somewhat shyly, hold hands. That is until Naru decides to arm wrestle.
Later, Naru wears a yukata that Haruka let her borrow, and cooks dinner for the two of them. As they eat, Naru looks at Keitaro and asks him for a favor. Keitaro thinks she wants him to kiss her, and he goes for it. Instead, she just wanted his plum, and Keitaro ends up bumping his head causing it to bleed. Naru puts a bandage on it, but catches Keitaro ogling her and gets angry. She ties him up and goes to take a bath, but as she does so the power goes out. Naru's afraid to take a bath by herself in the dark, so she drags Keitaro outside with her and warns him not to do anything perverted.
In the hot springs, Keitaro and Naru reminisce about the trip they took to Kyoto the previous year. Keitaro asks Naru if he can kiss her. They almost succeed... until Naru sneezes all over his face. As she wipes his face off, Naru asks Keitaro if he thinks they could visit Okinawa for a while. As if on cue, Mutsumi comes bursting out of the water, frightening the young couple. They had forgotten that she was still around. Mutsumi tells them that she's leaving to go home to Okinawa the next day, and she asks them if they want come along.
The other residents have arrived back at Hinata House, only to find that Keitaro, Naru, and Mutsumi have gone to Okinawa. In Okinawa, Keitaro and Naru are introduced to Mutsumi's mother and rather large family. Her mother seems to be as naive as she is. Against Keitaro and Naru's wishes, they are put in the single bed guest room. They try talk about things in the guest room, only to find Mutsumi and her mother doing reconnaissance on them. Mutsumi suggests they all go to the beach. While Mutsumi and Naru change into their swimsuits, Mutsumi asks Naru what her and Keitaro's plans are. She seems to be trying to get them together.
At the beach, Mutsumi pulls Keitaro aside and tells him that now is his chance with Naru. She gives him a "watermelon bashin' kit", and tells him to go for it. Keitaro and Naru put blindfolds on and try to bash the watermelon with sticks, but of course end up running into each other. Keitaro gets pummeled. Mutsumi then asks Keitaro to rub suntan lotion on her and he agrees. This makes Naru jealous, so she asks him to rub some on her also. Keitaro does so, tries to knock a sea cucumber off Naru's leg. He gets pummeled for his troubles.
Later, Mutsumi and Naru go swimming in the ocean. Mutsumi asks Naru how she feels about Keitaro. Naru somewhat embarrassedly tells Mutsumi that she likes Keitaro, but she wants to stay friends as long as possible because she's not any good at relationship stuff. She notices a giant clam and manages to change subject. They go to investigate, but the clam ends up clamping down on Naru's arm; trapping her. She tells Mutsumi to go find Keitaro, but amidst all the struggling, her bikini top comes off. Keitaro shows up, but Naru doesn't want him to see her topless and kicks him away. Mutsumi remembers something she saw in an old movie, and tells Keitaro that he needs to give Naru mouth to mouth. He goes back under and tries to give her air, but Naru(who has somehow managed to get her top back) passes out.
She wakes up, and Mutsumi tells her that Tama-chan talked the clam into letting her go. Naru apologizes to Keitaro and tells him that he was really something. Before she can go any further they discover Mutsumi's family spying on them again.
Keitaro is giving a speech to Okinawan children about what life as a Tokyo University student is like. His audience finds him hilarious, to Keitaro's consternation. Keitaro remembers that Mutsumi is also a Tokyo U student and he asks her why she didn't give the speech. It tuns out that Mutsumi had forgotten to tell her mom that she made it in.
Afterwards, Keitaro and Naru are in their room talking. Keitaro wants to tell Naru something, and she's afraid he's going to want to do something romantic. Instead, he just shows her a vase he found that resembles the ones on Parakelse. She tells him that he's clueless, and looks out the window to find Mutsumi's family spying on them. Again. Mutsumi tells them that her siblings need help with their homework. Keitaro agrees to help, only to find that they expect him to do all the work. While Keitaro is having trouble proving that he's smarter than a fifth grader, they kids start asking Naru personal questions; like how did she end up with Keitaro as a boyfriend(which she denies), who her first loves was, etc.. Mutsumi tells her siblings that Naru's first love was a boy she met at an inn, and that Keitaro's first love was a girl that he also met while staying at an inn. Keitaro has had enough and starts to chase the kids, while Mutsumi's mother tells Naru that she used to work at Hinata House years ago.
Later, Naru and Mutsumi go on a hayride, and as usual they end up talking about Keitaro. Mutsumi tells Naru that if she's not careful, Keitaro may end up being stolen right out from under her. She also tells her that she had her first crush on Keitaro also, but she decided to cheer them both on. She says that Naru doesn't have anything to worry about because her love for Keitaro is similar to her love for kotatsu and watermelons.
While they're talking, one of Mutsumi's little brothers comes up and tells them that Keitaro found something and for them to come quick. They arrive to find Keitaro stuck in a tree with two of Mutsumi's siblings. They had gotten stuck while finding beetles. Naru and Mutsumi try to get them down, but hijinks ensue. Keitaro ends up with his face buried in Naru's panties, and Mutsumi gets stuck in the tree with him while the two kids manage to get down. Naru takes the children to show off their beetles, and angrily tells Keitaro and Mutsumi that they can stay in the tree. While in the tree, the two reminisce about Haruka having to rescue them from trees when they were younger.
It's been a while, and Naru wonders why they're still in the tree. She walks up to find Mutsumi giving Keitaro a kiss.
Keitaro seems Naru below and tries to tell her that it's not what it looks like, while Mutsumi clumsily falls out of the tree and bumps heads with Naru. Naru is fine, but they have to take Mutsumi to the doctor. The doctor tells them that Mutsumi will be okay, but she has temporary amnesia, basically returning her mentally to when she was five years old.
They take Mutsumi home where she convinces Keitaro to play house with her. It's discovered that she's regressed back to the point to where she knows Keitaro, but before she met Naru. Anyways, they play house and manage to make Naru jealous. She manages to work her way into their playtime by pretending to be a baby, which causes Mutsumi to skip forward a little bit and remember her. While they're playing, Naru passes out and has a vision of their younger selves. Kei-kun and Mu-chan promise each other to go to Tokyo U. and leave Na-chan sick in bed. She awakes from her vision to find Mutsumi taking care of her. She realizes that Mutsumi has a fever, and Naru asks her was she taking care of her if she was so sick. Mutsumi tells her that she loves Kei-kun, but she also loves HER just as much. She then collapses to the floor.
The doctor explains that "since Mutsumi's younger self has taken root in the psyche of her adult body, the stress has built up to the point that she's no longer able to handle." ...Yeah. The doctor tells Keitaro and Naru that alternative medicine suggests that they may be able to cure her if they're able to fulfill some sort of wish that her younger self had. Mutsumi wakes, and they ask her if there's anything she wants. Of course, she wants to marry Keitaro. Keitaro agrees, in the hope that it will bring Mutsumi back to normal.
Mutsumi's family stages a faux wedding ceremony. Much to Naru's surprise, she can't contain her emotions and finds herself objecting to the pretend nuptials. Naru's embarrassed, and Mutsumi challenges her to a game of janken in which the loser has to give up on Keitaro completely. The first time ends in a draw as they both pull scissors. Naru has a flashback to her childhood, and remembers always losing at janken because the only thing she would choose would be scissors. Round 2 ends in a flash, and despite drawing scissors again, Naru wins! She realizes that Mutsumi must have let her win, and has another flashback to the same thing happening when they were children.
It's later. Mutsumi is back to normal, and the three of them are preparing to go back home. Naru tries to tell Keitaro that she now thinks that SHE might have been the one he made his promise to, but Mutsumi grabs Keitaro's head and kisses him. Naru ends up chasing Keitaro around the beach.
Keitaro arrives back at Hinata House, and Haruka asks where Naru and Mutsumi are. Keitaro explains that they've gone to the doctor for a checkup. He greets the other residents, and is surprised that Su calmly walks up, welcomes him back, and then runs off. Keitaro asks the other residents what's wrong with her. They don't know, but they tell him it started after he left for Okinawa. Keitaro go to Su and tries to cheer her up by offering her bananas and video games, but to no avail.
Keitaro and the other residents gather in the attic to figure out what's wrong with Su. Kitsune decides that Su must be in love with Keitaro. After being chased around the attic by Motoko for defiling Su, Keitaro leaves to go and talk to Su again. He asks her if she wants to go do something fun, and at first she declines, but Keitaro manages to convince her by telling her about a new restaurant that serves banana takoyaki.
At the restaurant, Su only nibbles on her food. She drops her mustard, and Keitaro picks it up for her. When he comes back up, he's surprised that she's wolfed down her food. Later, he buys her a cat outfit and they go to see a movie about a brother and sister. As they leave the theater, Su tells Keitaro that she's had fun and asks Keitaro if they can do this weekly. Keitaro reveals that he's been thinking about going overseas when the fall comes. Su starts to cry, detonates some bombs, and runs off. The other residents had been spying on them, and Motoko threatens Keitaro that she had taken an oath to kill anyone who had made Su cry. While they fight, Sarah calls Kitsune's cell phone and tells her that a gigantic hot air balloon has risen from Hinata House's courtyard. Sarah has a feeling that Su's going to fly back to her home country.
The gang arrives back at Hinata House and tries to talk to Su, but she won't listen. Motoko tells Keitaro that he has no choice, and throws him up and into the balloon. He lands on Su and discovers that she has a missing tooth. She tells him that her tooth fell out last week, and since then she hasn't received any letters from her brother. She's afraid that it's because he hates her now that her tooth fell out, and that this is also the reason Keitaro is thinking about leaving. Keitaro convinces her that this isn't the case, and she starts to feel better. Unfortunately, Keitaro accidentally hits the self destruct button. They manage to parachute to safety, and because it's a red moon, Su transforms into her adult self. Keitaro points out that her tooth has grown back, and they realize that it must have been a baby tooth. A block of text informs us that everything went back to normal and Su received a letter from her brother the next day.
Keitaro is having problems registering for classes. Because he had broken his leg, he never registered for classes the previous semester and now won't be able to advance. He laments falling so far behind Naru and Mutsumi and wonders how he's going to tell the other residents. They ask him what classes and clubs he signed up for; he lies and makes up several, including tennis.
Later, he goes to buy a racket for his fake tennis club when he runs into Naru. She knows that he didn't have any credits, and he starts to freak out. She tells him to calm down, and they get a bite to eat. Naru tells him not to worry, everyone eventually has to repeat a class. She's more worried with something Su told her, and asks Keitaro about his plans to study abroad. Keitaro tells her that he was thinking about it, but he wasn't really sure. Naru tells him that if it's something he really wants to do, then he should do it. Keitaro points out that if he does go, they'll be far apart. Naru looks uncomfortable and suddenly leaves, saying she has to get back to work. Keitaro is surprised, and asks what kind of job she has. She tells him that it's a secret, and leaves.
Later, Keitaro is browsing in a bookstore when he sees Naru walk by. She's dressed very professionally, and Keitaro decides to follow her. After several false stops, they end up in a classroom. Keitaro wears a disguise, and realizes that Naru must be tutoring the kids. Naru is nervous and makes a mistake on one her problems. The students laugh at her, but Keitaro manages to build up her confidence.
As Naru walks back home, Keitaro comes up and reveals that he was in her class. She chases him for a while, and then Keitaro asks her why she was teaching. Naru says that she was a bit jealous of him. He always got so excited talking about archeology, so she wanted to find something that inspires her. Back at Hinata House, Keitaro begs forgiveness from the other residents about lying earlier.
Naru is helping Keitaro study and she asks why he's studying stuff that was on the entrance exam month ago. He's about to tell her, but Su and Sarah come crashing in. They tell the studying couple all about the Yam Stew-Off and Halloween Party that Hinata House will be having. Shinobu interrupts and tells Keitaro that he has a phone call, which turns out to be his parents. They have found out that he doesn't have any class credits and want him to come home for a few days to discuss things. Sarah and Su are worried that he'll miss the Halloween Party, but Keitaro says he'll be back in four days, which is plenty of time. After he leaves, the older residents are happy that they won't have to put up with his peeping ways for a while.
A few days pass, and what started as relaxing has quickly become boring without Keitaro around. Finally, it's the fourth day, which also just happens to be Halloween. The gang dresses up in their costumes in order to surprise Keitaro when he arrives. They wait and wait, and finally there's a knock at the door. Unfortunately, it's Haitani and Shirai who have come to the Halloween party uninvited. They tell the Hinata House residents that Keitaro's family owns a famous candy shop, and his parents were always pressuring Keitaro to take over the family business. Shinobu starts to worry that Keitaro won't come back, but Naru reassures her that Keitaro always keeps his promises. The night passes, but Keitaro never shows up.
Two more days pass, and still no word from Keitaro. Naru gets angry and asks Haruka if she has his family's number. Haruka points out that when Keitaro first arrived, Naru kept going on about what an idiot he was and now they can't live without him. At that moment the phone rings. It's Keitaro. Naru yells at him for being inconsiderate, and they get disconnected. She's furious now and heads to the train station, planning to go to his family's house. As she arrives at the station, she runs into Keitaro coming out of a train.
He apologizes and tells her that his family made him work some of his debt off. Naru starts to cry, and tells Keitaro that she was worried about him. The other residents pop up out of nowhere and Keitaro gives them the gifts that he had brought back.
Keitaro is up doing some repair work on the Hinata House roof. He clumsily falls off, and ends up in the outdoor bath with Naru and Mutsumi. He tries to tell the two something, but Naru punches him and he goes flying. As he skids along the ground, he runs into Shinobu. She shows off the excellent grade she made on her test, and Keitaro gives her a card. He tells her to write down any special request that she has, and he will fulfill it. As she wonders what to ask for, Keitaro hands them out to the other residents and tells them that they'll expire on the 20th. Naru is curious about what he's planning, and goes to talk to him, only to find that he's repaired the hole in her floor that leads to his ceiling.
The next day at Tokyo University, Keitaro talks to Seta about an upcoming exam. Seta tells him that it's a remarkably hard exam; only six people will be accepted. If Keitaro is one of the six, he'll get to study with Seta. Seta then asks Keitaro if he's told everyone at Hinata House, yet. Keitaro says he's having a hard time breaking the news.
Back at Hinata House, Motoko and the other residents(minus Naru) confront Keitaro about American brochures they found in his room. On her card, Motoko has written "Tell the truth". Keitaro apologizes and tells them that he was hoping to study with Seta in America by the end of the month. He tells them that if he passes next week's test, he'll be studying archeology at the University of California for six months to a year. The other residents are furious and storm off.
Keitaro goes to his room; miserable. Naru crashes through his ceiling(she re-broke the hole in her floor), and asks him about the test. He apologizes and says she should have been the first person he told. She surprises him by giving him a plate of food and wishing him luck. Naru tells him that she understands how the gang feels, but she also knows how he feels, so she can't be mad. She tells Keitaro that the other residents do care about him, they just wanted him to be more honest. She then drags him outside to tell them how he feels. Keitaro shouts at Hinata House that he's sorry for being a jerk. Up until now he's been trying to fulfill a childhood promise, but this is different. This is something HE wants to do. As he asks Naru how he did, we see a shot of the other residents sitting silently in Hinata House.
A week passes, and it's the day of the exam. Keitaro is relaxing in the bath lamenting the fact that none of the residents besides Naru have talked to him. He is surprised when Shinobu enters the bath, followed by the others. They look angry and return the cards that he had given them. Keitaro looks at the cards and is puzzled to find that they all wish him luck. The residents smile and tell him to do his best. The issue ends with Naru grabbing him out of the bath telling him that it's time.
- Hinata 79: Kiss Kiss Kiss!
- Hinata 80: Bold Smooch In the Land of Everlasting Summer ♥
- Hinata 81: A Kiss Between Sea and Sky
- Hinata 82: Fuzzy Memories!?
- Hinata 83: For Whom the Wedding Bell Tolls
- Hinata 84: The Season of Maidenly Love
- Hinata 85:When She Puts On A Suit
- Hinata 86: One Week Later, I Miss You
- Hinata 87: Confession Time