After taking his daughter to the Salvatore Boarding House to comfort her, he hoped that she would marry one of the Salvatore Brothers. He was very upset at the illness of his daughter, so to make her feel better, he took her to Florence. Baron and Conte di Salvatore were friends, and the Giuseppe's kindness is shown when he cares for the Baron's daughter during his absence due to his position in the European nobility. Eventually, both men look the possibility of a marriage between Stefan and Katherine. But the return of Damon, cause behavior problems in Conte di Salvatore. Katherine decides to fake her death and solve the problems between the brothers, but in the end, the opposite happens, and kill each other. Baron is not mentioned in the following books, but he knew of the "death" of his daughter by her former servant.
In the television adaption, Mr. Petrov was a Bulgarian man who lived during the 15th century with his family and servants during his last days.
As Katherine's father, he was more rigid, cruel and cold, because she had a child out of wedlock, for this reason, Mr. Petrov was the first to exile his own daughter. This action caused the death of the Petrova Family, one year later. In Fifty Shades of Grayson, it was revealed that Katherine was a witch of the Traveler subculture stemming from her father.