Stories explaining the beginning of some particular behavior can be quite fanciful and equally unhelpful. This reference to a socially recognized relationship of marriage cannot later claim to be a justification for any specific claim, such as the privileging of heterosexual relations over a variety of other intersections of individuals or even singleness.
The only “father and mother” at this point is a creator carrying both what has come to be called masculine and feminine characteristics and passing them on through their image. These verses are a foreshadowing not an ontological claim of righteousness.
The ’adam of male and female in Genesis 1 and the ’adam carrying both within and needing to clarify both through division along the lines of a rib have a primary connection with their creator. The cascade of creation differentiation is about to reorient the story away from an initial creation to identify claims by individuals and groups.
As well as connecting “father and mother” to G*D in “one flesh” resultant from the “clinging” of man and woman to one another is not only a biologic, psychic, and spiritual bond but a resultant child. The two have become one, not as a reuniting but as a setting forth or calling forth of yet another creation and creator—a child.
This overly fanciful reading allows for the usual expectation to be fruitful and multiply to begin far in advance of the closing of Eden as a garden and its remembrance as a location and dream of eternity that will plague the rest of the story. In the imagery of Greg Brown, a focus on eternity has damn-near wrecked this place.
A difference between naked and unclothed introduces what can only enter later with a return to the earlier throwaway line about a tree of life and tree of knowing good from not-good. These verses are very meta-story and need to keep their appropriate place within a story and not be an explanation of anything.