Dai San Ouji wa Hakkou Butsu ni Tsuki, Chokushi Chuui

The young lady Lina originally comes from the wealthy count Randall’s family line. However, because of the bad weather that resulted in bad crops and because of her good-natured father, the family ended up being severely swindled. She quickly fell and became a poverty-stricken young lady. But then one day, Lina is forced to participate in the evening party to decide the fiancée of the third prince Gilberto... Since she stuck out like a sore thumb she decided to leave after she got a glance of the prince, but... What is that dazzling light behind the cheers of joy the young ladies are making...?!

(Source: Kadokawa, translated)