Dai go Koujo no Nariagari! Suterare Koujo, Koutei ni Narimasu

On the outskirts of the imperial palace of the mighty Tserbakia Empire stands the "Ghost Mansion"—the Palace of Fresh Greenery. It is a dilapidated, run-down estate inhabited by Yuzerika, the Fifth Imperial Princess, who was abandoned by her father, the Emperor. With her mother deceased and no powerful backers to rely on, she lives a frugal life, dedicating herself to managing the territory her mother left behind. Then, one day, the Emperor suddenly announces a "Crown Prince Selection Contest." Though initially shocked, Yuzerika realizes that becoming the ruler would allow her to exact revenge on the father who scorned them—so she decides to enter the race! The condition for victory is simple: "Amass wealth and enrich the nation over the course of three years." Believing that the era of building wealth through military might is over, Yuzerika focuses on human resource development and sets a certain plan into motion... Source: MU