Sezon 1

Nao Shirafuji and Takahito Kurose are coworkers and fierce rivals, competing for top sales every month. They might fight like cats and dogs at work, but they were actually lovers in high school! The cause of their breakup was a hurtful sentence he said during their first experience.

The story revolves around a man and a woman who have had the worst breakup in their lives and are now rivals in sales performance.