We could go even deeper...Have it turn out that the MC is actually a human from a very long time ago...A time when Giantesses did not exist...Because it turns out they are not natural beings, but artificial creations/experiments made by the people of the continent...It would explain why the mc does not seem as intellectually agile as humans are usually said to be(A stereotype that possibly came into being in recent times), why the giantessess have an unnatural magical and physical resisitance, why they have difficulties with breeding...Its cause they were designed this way