Koteibyou no Hanayome Sagashi

Uran, a girl from the countryside, moves to Tokyo to support her family, but is unable to find work and finds herself completely at a loss. One day, she arrives at a selection meeting for the caretaker of the Imperial Mausoleum...or so she thought, but it turns out the person being "selected" there is a bridal candidate for the Crown Prince!? (Source: Kadokawa, translated)