Tsubame Haruna (Suzu Hirose) is a female high school student. She spends her days peaceful, while concerned about other's facial expressions. She is forced to become the student president. Tsubame Haruna then meets Kei Shizukui (Ryunosuke Kamiki). He has a talented speech writer. With his help, Tsubame Haruna starts a revolution at her corrupt school.
Akiyama Shuntaro, a fourth-year university student who has had a good upbringing because his father is a member of the board of a well-known company, Shuntaro’s employment has somehow or other been determined with those connections and he spends his days aimlessly. Even though he questions his present way of life, he has not taken any constructive action. While on the way to uni one day, Shuntaro hits his head inside the train and loses consciousness, now he can see characters showing train station names in commuters’ heads. Then one day, he happens to see a man without a station name appearing above his head.
Yoshikawa Nao stays behind to live by herself when her parents leave to inherit her grandpa's farm in the country. On the day she moves into her new apartment, she discovers that it was rented also to Uehara Hisashi; a cute, super-cool, popular guy from her school. Not only did their housing agency unexpectedly close down, the landlord of the apartment tells them that they had to pay more for their apartment than they had expected. With no money and no home to return to, Nao and Hisashi decide to live together as flatmates.
Natsumi Uemura (Erika Toda) is an English teacher at Meiryo High School. She has always dreamed of being a teacher. Until her middle school days Natsumi lived in the U.S. She is now a first grade home room teacher and advisor to the basketball team. She is bright and has a positive character, so she is popular with the students. Shuji Kashiwagi (Haruma Miura) is a biology teacher at the same high school. Shuji is a 2nd grade home room teacher. Shuji is faithful and considerate. He deals with students with his heart so not only students but also their parents support him completely.
Natsumi and Shuji graduated from the same high school and university. They plan to marry in 3 months. Natsumi's friend and roommate, wedding planner Sayaka Todo (Mariko Shinoda), helps the couple with their wedding plans. All signs point to Natsumi and Shuji being happy.
On the first morning of the new school term, Shuji finds a naked woman sleeping next to him. Shuji thinks back to the prior night and recalls becoming drunk and having sex with the woman. He becomes embarrassed, but gives the unidentified woman a key and leaves for work. Shuji feels guilty to Natsumi and regrets what he did, but tries to calm down and prepare for the new school term.
Students in the 2 grade 1 class like Shuji as their home room teacher. When Shuji calls roll he discovers two students, Hikari Saeki (Emi Takei) and Nozomi Sonoda (Ayame Gouriki) have not yet come to school. At that time, one female student walks into the class room. The girl is Hikari. Shuji tells the students to move to the auditorium for the opening ceremony of the new school term. Hikari stays in the classroom until the rest of the students clear out. Hikari gives something to Shuji. The item is Shuji's apartment key. Shuji realizes the woman he spent with last night is Hikari...
Sixth grader Ayase Chihaya, a tomboy with no ambitions or goals of her own, gets to know Wataya Arata, a transfer student at Chihaya's elementary school and an outcast. Through Arata, Chihaya picks up karuta and they form a team with their other friend and classmate Mashima Taichi. After graduating elementary school, Chihaya continues to play karuta hoping for a chance to meet Arata again after he went back to Fukui to take care of his sick grandfather. As time passed and Chihaya enters high school, she starts a karuta club with Taichi so that they can finally meet Arata again.
Mihane Yoshiyama (Yuina Kuroshima) is a 3rd grade high school student. She is a member of the photo club at her school. The day before her summer vacation, she smells a lavender scent in the science lab and she suddenly gains the ability to leap through time. Shohei Fukamachi (Fuma Kikuchi) is Mihane’s classmate. He actually came from the year 2122 and is a researcher. Shohei lost a drug that allows him to go back to 2122. In the meantime, Shohei hypnotizes those around him and lives as a high school student.
Mihane and Shohei become to have feelings for each other.
Tooru Igarashi (Kotaro Koizumi) is a lecturer with charisma, working at a prestigious preparatory school. Recently, he drinks a lot and his life falls apart. Maki Endo (Haruna Kawaguchi) is a student at a part-time high school. Every day, she is exhausted with working multiple jobs to cover her expenses. One day, Tooru and Maki happen to meet each other. Maki wants to graduate high school to get a regular job and asks Tooru to tutor her for her test–retest. After Tooru quit his prep school job, he has lost his pride and passion to teach. Tooru was also diagnosed to have only a year left to live. He decides to teach Maki and get her into the University of Tokyo.
Koichi Hikuma (Akira Terao) was a saxophone player, but he suffers from the aftereffects of an accident. Due to that, he turned his back on music. Koichi Hikuma finds hope in the high school brand band. The band consists of problem students. Koichi struggles to instruct the brass band and to give them hope.
Yuiko Yoshioka (Mei Nagano) begins the first grade in high school. She gets sick with the cold and stays in bed. At that time, she gets a phone call from class president Matsubara. Yuiko becomes fluttered by his kind voice on the phone. The next day, she goes to school and meets Matsubara. He is a mysterious boy, wearing a paper bag over his head. Her high school days begin with pounding heart.