Hatsukoi no Onzoushi to Gisou Kekkon Shimashita

I need you to find me someone to marry right away.
Miyuki Fujisaki, who works at a marriage consultation center, is visited by none other than Sou Takeda, the heir to one of Japan's largest business conglomerates. And just between us, he's her first love who she had secretly adored from afar. Unaware of such feelings, Sou chooses Miyuki as his bride for a three-month contractual marriage. Thus begins a sham marriage under the same roof as her first love! How will it all turn out?!