On the same day, he happens to meet Erika Amano, a high school girl who attends a prestigious girls’ academy. It turns out that Erika’s parents are forcing her into an arranged marriage. To put the brakes on it, she more or less forces Nagi to be her fake boyfriend.

However, much to their surprise, Nagi and Erika were the two babies swapped at birth and Nagi is Erika’s fiancé! Coming from a place of love and wanting to officially make them part of both families, their parents make special arrangements for the couple-to-be to live together.

Now being forced to live together, they must figure a way out of this sticky situation. Nagi has no intention of marrying Erika because he has a crush on his classmate, Hiro Segawa, and Erika wants nothing more than to rebel against her father. So, the two of them strike up a deal and promise to never get involved with each other.

Follow this new romantic comedy as the complicated lives of this mismatched couple begin!