An Officer and a Princess(2009)

Princess to Kekkon?

The Kingdom of Edenbourg is shaken with the king's disappearance. Princess Isabel decides to rescue her abducted father on her own. She plans to slip into a pub to find clues, posing as a married couple with Lieutenant Adam. "I will count on you when I get into trouble," the princess says to Adam, who tries to stop her because it is too dangerous. Adam prepares himself for the mission instead. On the day of the investigation, at the pub, Adam finds Isabel dressed so luscious that she looks like a loose woman!

(Source: Digital Manga Publishing)