Love Generation revolves around the relationship of the two leading protagonists, Katagiri Teppei and Uesugi Riko, who begin their relationship as squabbling colleagues before falling in love.
Katagiri Teppei is an advertisement designer, but he's forced to be transferred to the Sales Department because of his egocentric behavior. He is forced to adapt to a new working environment, which includes changing his appearance to create a more professional image as a salesman. He runs into Uesugi Riko at work, who always fights with him, and his high school sweetheart, Mizuhara Sanae, whom he still loves only to find out that she's engaged to his brother, Soichiro. Things take an unexpected turn between them and later on leads to a complicated love triangle.