DASS-709 _Desire for the new bride's body

Nanase Alice is a beautiful young girl with a bright future because her father is the president, so Nanase. Like other teenage girls, Nanase is dating Takashi, an enthusiastic young colleague who is devoted to Nanase's father's company. While the young couple was immersing themselves in happy days and dreaming about a dream marriage, Nanase's father's company was being played by a competitor and was at risk of bankruptcy. Fortunately, Takashi's father, Mr. Toru, is a quite wealthy investor, so they came to him for help. Toru agreed to invest a large sum of money but on the condition that Takashi and Nanase must immediately get married. So Nanase became Toru's daughter-in-law and their marriage saved Nanase's father's company. Actually, what is the main reason why Toru did this?