There is no such thing as bad luck for a daughter to bring her boyfriend home. Daughters bring their boyfriends home mostly because they want their parents to witness their love, and they also hope their parents can bless their love. This matter does not violate morality or law, so it has nothing to do with Feng Shui.
It is really sensitive for girls to bring boys home to live, because everyone has higher requirements for girls and thinks that girls can't be with men casually before marriage. If a girl is found by people around her, and finally the girl is not with the boy, everyone will look at the girl with colored glasses, which will also produce certain rejection to the girl. Therefore, when girls bring a boy home, they must consider whether they will marry this boy, or whether this boy will affect their family harmony, and don't do anything immoral.
Feng shui is an invisible thing. If you want to have good luck all the time, you should only do what is permitted by law and morality, and do more good deeds instead of doing things that make you feel guilty.