Taishou Itsuwari Bridal Migawari Hanayome To Gunpuku No Mouai Episode 4

Touno Asako is the eldest daughter of a count who has been ostracized from the circles of the top ten thousand for some time. One day, he learns that his ailing sister Hiroko has received a marriage proposal from Captain Kidou Shintaro, who has a reputation for being cruel and heartless, and is rumored to be looking for a bride only to bear the child for him. To protect her precious little sister, Asako volunteers to be a surrogate bride.