is a Japanese manga series written and illustrated by Mizuki Kishikawa. It began serialization on Shueisha's "Shōnen Jump+" manga service in October 2023.
Plot.
As a junior high school student, Sunao Akiyoshi was in a relationship with his childhood friend Lemon Nishikawa. One day, Lemon confesses to Sunao that she has been cheating on him with three different men and breaks up with him. Since that day, Sunao has struggled to move on from Lemon, but despite that he has moved on to university and is trying to start a new relationship with fellow student and film club member Natsumi Kogahara. He later unexpectedly reunites with Lemon on an outing. The next day he wakes up in Lemon's body, and Lemon shows up in Sunao's body. Sunao later discovers that Lemon is a student at a top-tier school and that she is roommates with Kogahara.
The main protagonist. Ever since the end of his relationship with Lemon, Sunao has been haunted by nightmares of her. He's trying to start a relationship with Kogahara, and ends up going on a date with her, but his plan was inconvenienced by the sudden body swap with Lemon, forcing Lemon in Sunao's body to go on the date with Kogahara. 
The main female protagonist. She was excited when she reunited with Sunao years after her breakup. Lemon was popular in junior high school and her popularity continues in university. When the body swap happens, she decides to keep the body swap secret and help him in his effort to start a relationship with Kogahara. It is later revealed that when Lemon broke up with Sunao, she had lied about cheating on him, and that she still has feelings for him.
The target of Sunao's affection, Kogahara is also a former high school senior and current roommate of Lemon Nishikawa. She's a member of her university's film club alongside Sunao.
Sunao's close friend at university. He's also a member of his university's film club alongside Sunao and Kogahara. He's logical and rational and had a crush on Lemon, before finding out about Sunao and Lemon's secret.
A fan of Lemon who knows Sunao and Lemon's secret.
Publication.
Written and illustrated by Mizuki Kishikawa, "Hope You're Happy, Lemon" began serialization on Shueisha's "Shōnen Jump+" manga service on October 15, 2023. Its chapters have been collected into six "tankōbon" volumes as of April 2025.
The series' chapters are simultaneously published in English on Shueisha's "Manga Plus" platform. In January 2025, Seven Seas Entertainment announced that they had licensed the series for English publication with the first volume releasing in October 2025.
Reception.
The series was nominated for the 10th Next Manga Awards in 2024 in the web category and was ranked fourth.