The term "who" needs to be changed to "what", and then the answer is that two thirds of Creation is Esoteric [which means it is not physical] and thus it is protected by being inaccessible by anything that is not itself Esoteric
Those who do God's will protect the universe because they justify its existence (Talmud, Berakhot 6b).
Humans have been given the role of caring for creation on earth.
Protector of marriage
Me
God is the creater,protector,omnipotent,omnipresent.
In Revelation chapter 12, the woman is the nation of Israel, and her protector is God.
Freyja
God saw the creation and said that it was good.
Ptah is the ancient Egyptian god of creation.
Jesus
The name of the Egyptian's god of creation is Ptah.
Bona Dea
There are a number of Latin words that can be translated "protector", including patronus (as in Harry Potter's exspecto patronum, "I await a protector") and vindex(as in the Confederate motto Deo vindice, "with God as protector").