Warum lügt Fräulein Käthe?

The story

The pleasure boat “Milwaukee” has a wide variety of guests on board: Frau Deiters, who is determined to get her daughter married off; Herr Krueger, who won a free ticket to travel onboard; Herr Dr. Bornemann, a completely introverted man, who has dedicated himself to his work; and Ms. Kathe, the ship’s photographer. On the way to Madeira, Mother Deiters quickly determines, that only Dr. Bornemann would be an appropriate match for her daughter. However, Fraulein Kathe secretly is in love with him. When the two end up in a very publicly embarrassing situation, the entire ship thinks she is the fiancée.