Chocolate Cosmos (チョコレートコスモス Chokorēto Kosumosu?) is a Japanese shōjo manga series written and illustrated by Nana Haruta. The series was serialized in Ribon magazine from the September 2007 issue of the magazine until its final chapter in the November 2008 issue. The individual chapters were collected into four tankōbon volumes by publisher Shueisha; the first on December 14, 2007 and the final on November 14, 2008.
Sayuki Sakurai is a sixteen year old girl who is determined to find love. On a trip to the beach she meets a handsome man who smells like chocolate and falls in love with him immediately. He tells her that he goes to her school and she is left puzzled as she has never seen him before. When she returns to school she has a surprise in the form of Hagiwara-Sensei, her Home Economics teacher!
- Sayuki Sakurai (桜井 紗雪 Sakurai Sayuki?)
- The protagonist, a first-year at Shunei High School who hopes to find true love, but has a perpetual and innate grumpy look on her face, which causes people to mistake her as bully. She's never had a boyfriend. She falls in love with her teacher, Hagiwara-sensei, without knowing his true identity. Although she claims to hate Yūshi, her actions prove otherwise.
- Katsuya Hagiwara (萩原 克弥 Hagiwara Katsuya?)
- The Home Economics teacher beginning his first year teaching at Shunei, he is young and handsome. Because of this, a good deal of students are infatuated with him to various degrees. He is an advisor for the baseball/culinary club that Yūshi and Sayuki start. Though he was her teacher before then, he "meets" Sayuki at the beach during summer vacation, where he rescues her from a date. He never tells her his name, but says he goes to the same school as her. He is very kindhearted and outside of school is an average guy. He covertly looks after Sayuki.
- Mina Nomura (野村 美奈 Nomura Mina?)
- One of Sayuki's friends, Mina is outgoing and boy crazy. She tries to help Sayuki find a boyfriend by taking her to the beach and to a basketball game.
- Shiori Harada (原田 栞 Harada Shiori?)
- Another one of Sayuki's friends, Shiori is very mysterious and quiet. She is observant and reluctantly supports helping Sayuki through dangerous and occult methods.
- Yūshi Mutō (武藤 悠士 Mutō Yūshi?)
- A boy in the same grade as Sayuki, and her lifelong friend. He likes to read baseball manga, and tries to start a baseball club, which soon becomes a baseball/culinary Club. Yūshi has a crush on Sayuki and goes out of his way to impress her.
- Takayuki Kaji (梶 高行 Kaji Takayuki?)
- Yūshi's narcissistic best friend, and heart-throb of the first year class, Kaji is handsome and slightly air-headed. He tries to help Yūshi catch Sayuki's eye, and encourages the idea of a baseball club.
Written and drawn by Nana Haruta, the Chocolate Cosmos manga began serialization in the shōjo manga magazine Ribon on August 3, 2007 in the September issue of the magazine. The series ended on October 3, 2008 in the November issue of the same magazine. The series is licensed by Sharp Point Press in Taiwan. It is also licensed by Tokyopop Germany.