Marmalade Boy is a Japanese romantic comedy-drama anime film released in 1994, based on a manga series of the same name by Wataru Yoshizumi. The story revolves around two families who divorce their respective partners and marry each other, leading to the two sets of children becoming stepsiblings. The movie primarily focuses on the relationship between Miki Koishikawa, the 16-year-old protagonist, and her stepbrother, Yuu Matsuura.
Miki is a normal high school student who had always lived with her parents until they suddenly tell her that they are getting a divorce. Shortly after, they reveal that they plan to swap partners with another couple, the Matsuuras, whom they had met during their trip to Hawaii. The two parents fall in love and decide to remarry, which means that Miki and her little brother will have to live with the Matsuuras as their new family.
Miki initially resents this whole arrangement, as she is disturbed by the idea of having a new stepbrother in Yuu. However, things take a surprising turn when she meets Yuu, who is the same age as her and shares similar interests. They quickly become friends and start spending more and more time together, leading to a budding romance between them.
As the movie progresses, Miki and Yuu's relationship becomes complicated as they both struggle with their feelings for each other. Matters are further complicated by the arrival of new love interests in the forms of Ginta, a fellow classmate of Miki's, and Arimi, Yuu's ex-girlfriend.
Marmalade Boy is a heartwarming and at times emotional movie that explores themes of family, love, and growing up. It features wonderful animation and a catchy soundtrack that complements the sweet and engaging story.