Mischievous Kiss

Kotoko Aihara, a senior student with poor grades, has been secretly in love for two years with Naoki Irie, an IQ200 genius in her school. After handing a love letter to Naoki, Kotoko was rejected. Additionally, the new house of Kotoko and her father was destroyed by a Meteor shower. She had to stay at her father's best friend's place,however.

Kotoko moved to Naoki's house, but he's as cold as before. Naoki's mother Noriko, on the contrary, has always wanted a daughter and thus welcomed Kotoko excitedly. Kotoko received a photo of Naoki from Noriko, a photo of young Naoki dressed as a girl. Using the photo as a leverage, Kotoko blackmailed Naoki, making him to help her with her study to be within Top 100 in the final exams.

The whole school knew about their living-together, making Naoki extremely displeased and even treating Kotoko more coldly. Kinnosuke sneaked into Naoki's house yet confronted with Naoki saying "I don't like her today but may like her tomorrow", which gave Kotoko a new hope. On the last day of the summer vacation, the whole family went out, leaving Kotoko alone with Naoki for the night.

Kotoko decided to join Tonan University through internal evaluation. However, Naoki, without knowing what to do in the future, decided to try the National Center Test for University Admissions. On the exam day, Naoki, thanks to Kotoko's handmade amulet, had a terribly unlucky day. On the day of the entrance exam for Tokyo University, Kotoko went with Naoki to the exam site.

The graduation ceremony. Naoki also decided to join Tonan internally. Kin, who was unable to go to university, decided to start working for the future with Kotoko. Class-F and Class-A happened to book the same location for testimonial parties, ending into a nerve-kicking mode. Eventually Naoki began to tease Kotoko in front of everyone, and in return Kotoko exposed Naoki's girl-dressing photo.

Nothing has happened between Kotoko and Naoki since the kiss. University life began, and Kotoko found herself facing a quite competitive rival - Yuko Matsumoto. Since they were in different schools, anxious Kotoko joined tennis club so as to get closer with Kaoki. One night, Kotoko, told by her father to leave the Irie house to give up her desire for Naoki, was shocked.

Kotoko left Irie's house, making up her mind to give up Naoki. However, while participating in the tennis club, Kotoko had to double with Naoki and play against Suto and Matsumoto. Naoki, losing his first game in life regretfully, decided to train Kotoko. On the other hand, Noriko, missing Kotoko, sneaked into the university and got to know that Naoki and Kotoko had kissed.

With Noriko's effort, Kotoko moved back to Naoki's house. Noriko encouraged Kotoko to go on a date with Naoki, but Naoki went out with Matsumoto. Kotoko teamed with Suto, a senior student who admired Matsumoto, and followed Naoki and Matsumoto. On the other hand, Kinnosuke, mistaking that Kotoko went on a date with Suto, rushed out to search for Kotoko.

Kotoko, pleased that Naoki told her he didn't hate her, was soon displeased because Naoki moved out to start living by himself. Kotoko rushed to Naoki's part-time workplace, gaining no useful information. One night, Kotoko followed Naoki and witnessed him getting into Matsumoto's place, believing they have been living together, heart-broken. Naoki noticed Kotoko's unusual behavior.

Parents went out, leaving Kotoko and Yuki to take care of the house. However, Yuki suddenly felt a terrible stomachache. Kotoko was terrified but could manage to get over the pinched nerve. Kotoko was relieved as Naoki went to the hospital shortly afterwards. Due to the heavy snow, Kotoko had to stay at Naoki's place. Unexpectedly, Naoki confessed to Kotoko.

Christmas Eve. Kotoko originally planned to celebrate with Satomi and Jinko, yet they both had to cancel at last minute, leaving Kotoko all alone at home. While Naoki was on his way to the party of Shigeki's company, he saw Jinko with her boyfriend. In the meanwhile, Kinnosuke saw Satomi came to "Aihara" restaurant with her boyfriend.

Kotoko became a sophomore. While her friends have been working hard for their dreams, Kotoko was anxious as she had no idea about what exactly she wanted to do in the future. One night, a family party was held at Irie's house. Naoki was angry upon learning that his father wanted him to take control of the company, walking out of home. Kotoko went after him and learnt about his dream.

Shigeki was hospitalized by a heart attack. As a result, Naoki went to take care of the company, learning that the company's business status is worse than he thought. Kotoko was worried about Naoki, not only because he had to leave school, but also that he had to give up his dream of being a doctor. In the meanwhile, Matsumoto made up her mind to reveal her affection for Naoki.

While Kotoko felt that her heart and Naoki's were getting closer, she was shocked to know that he went on a formal marriage matchmaking. He was introduced to Sahoko Oizumi, grand-daughter of Hokueisha's chairman who was considering investing Shigeki's company. Noriko, intimidated by the appearance of a perfect lady, practiced with Kotoko in order to crash the matchmaking.

With marriage in mind, Naoki began to date Sahoko. On the other hand, Kotoko went on a date with Kinnosuke. Although the date made her happier than expected, Kotoko was still thinking about Naoki. One day, Shigeo told Kotoko that, in order not to disturb Naoki and his marriage, she should move out of Irie's place. Kotoko believed it's time to truly give up Naoki, tears running down her face.

Kotoko told Satomi and Jinko that Kinnosuke asked her to marry him, while they asked Kotoko to seriously think over being together with him. Naoki, who got engaged with Sahoko and began to prepare for the marriage, went to the university and learned about Kinnosuke's proposal. Just at that time, Kinnosuke was waiting for Kotoko's answer.