A Couple of Cuckoos

Nagi Umino, who was switched with another family's baby at birth, is about to meet his biological parents. On the way, he encounters Erika Amano, a wealthy student who pressures him into pretending to be her boyfriend so she can avoid an unwanted engagement.

They discover that they were the babies switched at birth, and their families have arranged for them to marry. The two begin living together despite wanting no part in the arrangement. Nagi already loves his classmate Hiro Segawa, while Erika wants to resist her father's plans, so they agree to keep romance out of their new household.