The Invisible Wallflower Marries an Upstart Aristocrat After Getting Dumped for Her Sister!

Iris, the daughter of a marquess, not only had her fiancé stolen by her younger sister, but she also ended up having to marry Lord Lucas, a nouveau riche merchant who was shouldering her family's debts. However, this former-commoner-turned-baron's reason for marrying her was just to have Iris teach him and his servants how to survive in high...