In order for my little excerpts at the beginning of each chapter to not be too confusing, I wanted to list as to what title represents what character.

Crown Prince - the Male Lead, Zhang Yi Chen

Elder/First Princess - the Female Lead, Lu Zhi

Prince/Son of Grand Duke - the Second Male Lead, Lin Ming Ze

Younger/Second Princess - the Second Female Lead, Lu Ying

King & Queen - ML's parents

Emperor & Empress - FL's parents

Kingdom is in reference to the Zhang's business group and Empire represents Lu's business group.