Princess Eclair

Princess Eclair was the damsel-in-distress that Luigi rescued from the clutches of the monstrous Chestnut King in the Waffle Kingdom. However, as it turns out, Princess Eclair was actually the king's lover, who had been turned into a monster by the sinister Crepe. This story is told by Luigi when Mario talks to him throughout the events of Paper Mario: The Thousand-Year Door.

During Luigi's adventure, the green-clad plumber fell in love with Princess Eclair. However, after he discovered that the Chestnut King was Princess Eclair's fiancée, Luigi lost the hope of ever forming a romantic relationship with the princess. Since Luigi embellished his stories so much, it is unknown whether any of it really happened as he described (or whether she even exists at all.)

She is also mentioned in Luigi's five-book series Super Luigi, which is sold in Paper Mario: The Thousand-Year Door.