Dear Sir, to Us Who Were "Ice Knight and Mediocre Princess"

The sickly and socially withdrawn Princess Ridelle fell in love with the quick-witted knight, Sir Oscar and became his wife. But after finding out that Oscar didn't wish for the marriage, their marriage life became no different than a pile of misfortunes.

Soon, Ridelle was struck down by another tragedy, changing both of their lives tremendously, but...

This is the love story between a former princess who was looked down upon as "the Failure Princess," and the young count known as "the Ice Knight"—the crossing of their paths weaving tragedies in their wake.