started off as a trend which describes the strange combinations of food popularly women or men eat. ie plain pasta with butter or pickles and peanut butter which a choc nesquick milk. (similar to depression meals in the sense that they are lazy and quick meals)
using this context it is now used to describe someone attractive who has a plain/mediocre look to them however, can easily be ‘devoured’ due to their appearance
whatever a girl wants to have for dinner
it could be a person, an object, an activity, or actual food.
it's not about literally feeding yourself with said thing, just consuming or doing it.