Definition of have one's cake and eat it too in English English dictionary
To seek to have two things which are mutually incompatible (such as eating a piece of cake and yet still possessing that piece for future use)
Do you seriously want to break up with her and still have sex with her? You can't have your cake and eat it too!.
(deyim) To wish to have one's cake and eat it too or simply have one's cake and eat it (sometimes eat one's cake and have it too) is to want more than one can handle or deserve, or to try to have two incompatible things. This is a popular English idiomatic proverb, or figure of speech