Monthly Girls' Nozaki-kun

Chiyo Sakura, age 16, tells her crush Umetaro Nozaki that she is his fan, but he responds by giving her his autograph. She then says she wants to be with him always, so Nozaki invites her home and gives her some "beta work", which after several hours, she realizes she is doing inking for him. She realizes he is a shojo manga artist who is published in a magazine she has bought. Later, they think of romance ideas such as making a guy a delinquent but should obey the laws, and taking a girl home with a bicycle. Nozaki invites Sakura home but he has a tandem bicycle, so they see if any of the situations are conducive to romance. After seeing him interact with some cats, Sakura tries to confess her love again, but gets another autograph. Nozaki introduces Sakura to his friend.

Nozaki introduces Sakura to his friend Mikoto Mikoshiba, a popular and flirtatious guy who Sakura soon learns is actually painfully shy and is often ashamed of his own words. He spends a session at Nozaki's place eagerly waiting for Sakura to ask him for help although he is too shy to prompt her. Sakura learns that Mikoshiba's artistic specialty is adding background decorations such as flowers, and she discovers that Mikoshiba is Nozaki's model for the heroine of his manga. Nozaki later asks Sakura if she has any friends who might fit in a shojo manga. Sakura introduces them to Yuzuki Seo, a girl who the guys discover has a habit of being insensitive and oblivious (not reading the atmosphere). However, she has an angelic singing voice, of which she is nicknamed the Glee Club's Lorelei.

Mikoshiba introduces to Sakura and Nozaki his best friend, Yū Kashima, who is known as the school prince, but is actually a girl. She is a member of the acting club and is really popular among the girls. However, she is a bit dense and acts idiotic sometimes that her senior at acting club Masayuki Hori will scold and even physically beat her. After helping Hori paint some sets, Sakura discovers that he is the one who does backgrounds for Nozaki's manga. When Mashima sees Hori with Nozaki, she gets a bit jealous. Nozaki later has Hori and Sakura role-play some parts, during which Mikoshiba also gets involved.

Mikoshiba asks Nozaki if he can stay over in order to seek his advice regarding girls, however the "girls" turn out to be heroines of a dating simulation game. As they try out the game, they realize that the protagonist's best friend, Tomoda, has been caring for him throughout his adventures, which prompts Nozaki to make a story about their friendship, which appears to Sakura to be a Boy's Love-genre story. Later, Mikoshiba is invited to attend a mixer but is too shy to know what to do there, so Nozaki and Sakura practice with him.

Nozaki frantically cleans his apartment for his editor, Ken Miyamae, who appears and leaves so quickly that Sakura thinks he does not like Nozaki. However, Nozaki praises him in comparison to his previous editor Maeno, with whom he had bad experiences. Sakura meets Nozaki's neighbor, Yukari Miyako, who also draws manga in the same magazine, and later meets Maeno himself. When Ken tells Nozaki that the heroine of the manga should express more feelings, Nozaki pretends to act like the heroine for the day by giving lunches to his friends and carting Kashima away from a mob of livid girls. He concludes that Mamiko needs to study more and draws that into his storyboards.

Nozaki sees Hirotaka Wakamatsu, his junior from middle school when they were on the basketball club. Wakamatsu tells Nozaki about being stressed out and unable to sleep because of Seo's antics, however, when he hears a recording of Lorelei's singing, he immediately falls asleep and feels refreshed. Using Nozaki's shōjo manga as a basis, he confronts Seo, but she interprets his actions as gestures of friendship. Later on, Nozaki gets a fever and sends the text message "SOS" to Hori, Sakura, and Wakamatsu. The three team up to help Nozaki with his manga, but are challenged with the task of applying screentones.