Mahoraba ~Heartful days~

Ryushi arrives at his new apartment complex, where the landlady is his second cousin, Kozu, who is also in high school. He quickly develops a crush on her, but when she trips and falls on him one day, she suddenly becomes a totally different person!

Not only is Kozue suddenly acting like a delinquent, but she also doesn't even know who Ryushi is! His neighbors, Megumi and Tamami, rescue Ryushi from a beating. He learns that when Kozue gets a shock, she's taken over by a different personality, Saki.

After Kozue faints from embarrassment due to the wind blowing up her skirt, she wakes up with a shy and childish personality, Nanako. The other residents make Ryushi babysit Nanako, and she proves to be quite a handful.

Ryushi goes to art college for the first time and meets his elegant but terrifying teacher, Miyabi. On the way home, he runs into Kozue and Tamami. They go to the park and encounter a maid, then help her search for her missing stamp card.

Ryushi follows a trail of petals to find the perpetually depressed Sayoko, who earns a living by assembling artificial flowers and doing other odd jobs. He ends up helping her and her cheerful daughter Asami make flowers while learning how they live.

Tamami barges into Ryushi's room and, using a compromising photo, blackmails him into helping her. She makes him come to her high school and carry her bonsai tree home while revealing the limitless depths of her mischief.

The residents of Narutaki-so organize a game of hide and seek, with a ticket that lets the winner make any request they wish as the prize. Ryushi sees his chance to finally stop their endless parties. Can his determination match their cunning?

Ryushi goes on a shopping trip with Kozue, and Megumi and Tamami sneak out after them. Then Kozue's taken over by Saki in the middle of the department store! After the usual misunderstandings, Ryushi finally sees there's more to Saki than her violent side.

Another wild party leaves Ryushi deep asleep, and when he wakes up, Megumi and Tamami have dressed him in women's clothes! He tries to escape before Kozue sees him, but instead surprises her and makes her faint. She wakes up as a new personality, Chiyuri, who's a cosplay maniac!

Miyabi, the art teacher, assigns a drawing of a person as homework. Ryushi's classmates come to his place to do it, where they use Megumi and Sayoko as models. When Kozue and the other residents get back from shopping, they draw them as well.

After struggling to write a letter without success, Megumi goes out and runs into Ryushi in the shopping street, where she makes him go on a date with her. They go shopping and see a movie. In the end, she reveals her true motivation to him.

It's incredibly hot, and the Narutaki-so residents decide to go to the beach. They have fun in the water together, split a watermelon, then hold a seafood barbecue. At the end of the day, Kozue and Ryushi watch the sunset together.

Kozue discovers the diary of her great-grandfather in the storage room, and inside it is a treasure map! Everyone works together to solve the clues. But the treasure at the end isn't what any of them were expecting...

Ryushi's homework is a picture book, but the end of summer break is approaching fast and he still has no ideas... until he sees Kozue talking to a sprout as she waters it. He searches for extra inspiration by watching the Narutaki-so residents.

After Kozue's latest personality surfaces and runs away from them without a word, Ryushi and the others try to develop schemes to convince her to talk to them. Their wacky plots fail, but can Ryushi's patience succeed?

Miyabi, Ryushi's teacher, unexpectedly asks to see his home. Then Asami brings her friends from school to visit. And as if that weren't enough, the leader of Tamami's occult club attempts to break through her spiritual barrier and invade Narutaki-so!

Tamami reminisces about the time before she met Kozue and the reason why she became such good friends with her. She wonders if Ryushi has replaced her in Kozue's heart, but life holds surprises even for her.

Kozue finds two kittens wandering around the apartment. When one of them surprises her, Saki takes over! Surprise after surprise leads to all of Kozue's personalities coming out and a chaotic day for Ryushi.

Ryushi's homework assignment leads to him wondering how the other residents of Narutaki-so spend their day. One by one, he finds out what their daily lives are like. But is Ryushi the only one who's curious about that?

Kozue's school is holding a festival, and she invites all the residents. At the festival, they go around and enjoy the exhibits. When the members of the orchestral music club beg for their help, Megumi and Sayoko shock them all with their hidden talent.

A strange girl and a maid arrive at Narutaki-so and take Asami and Sayoko away with them! They take them back to a mansion, where Asami meets Sayoko's father and mother, and finally learns the truth about her mother's past.

Sayoko's parents try to convince her to part ways with Asami, while elsewhere, the Narutaki-so residents realize how much Sayoko and Asami meant to them. Asami tries to intervene, but it's Sayoko's determination that saves the day.

The Narutaki-so residents decide to go on a picnic to see the colorful autumn leaves. They almost leave Asami and Sayoko behind, drink a lot of beer, and play tag. It's all par for the course in Ryushi's wildlife!

Ryushi gets a part-time job at a grocer. Then he trips and falls in front of a truck, causing an accident. He's unhurt, but the shock of hearing about it makes Kozue fall unconscious!

Kozue wakes up again, but as the boisterous Saki! The residents try to shock her into being Kozue again, but only her other personalities come out. Tamami confronts Ryushi and tells him what needs to be done to save Kozue.