Why?
Because otherwise, there's no parallel. There' just isn't a "virgin birth" other than Jesus' anywhere in antiquity. Nowhere. The dignified act of creative fiat illustrated by Matthew and Luke offers no parallel to pagan accounts of women inseminated by gods disguised as swans, fruit, lightning bolts, and so on (he even uses Romulus, born of a vestal virgin who was raped!). No divine sex. It's creative fiat, the same way that the creation was arrived at in Genesis. In this light we see no need to offer more than a few comments on this part of Pikachu's uber-sermon. His equivocation with terms above as much as admits to his lack of success.

Now this Apis, or Epaphus, is the calf of a cow which is never afterwards able to bear young. The Egyptians say that fire comes down from heaven upon the cow, which thereupon conceives Apis. The calf which is so called has the following marks:- He is black, with a square spot of white upon his forehead, and on his back the figure of an eagle; the hairs in his tail are double, and there is a beetle upon his tongue.
[Herodotus 3.28] Yes, one example of the sort of thing Pikachu uses in his "virgin birth" section. Do you see a virgin? I sure don't.

One example worth comment is that of the godman Dionysus who was the Son of Zeus and the mortal Semele. Well, depending of what story you believe. There are several. But it's so obviously not "virgin" as to be painful:

I am Dionysos, the son of Zeus,
come back to Thebes, this land where I was born.
My mother was [the king] Cadmus's daughter, Semele by name,
midwifed by fire, delivered by the lightning's blast.
And here I stand, a god incognito, disguised as a man.
[Euripides, The Bacchae, v 1 - 5 (5th century BC)]

And Semele, daughter of Cadmus was joined with him [Zeus] in love and bore him a splendid son, joyous Dionysus,--a mortal woman an immortal son. And now they both are gods.
[Hesiod, Theogony 940, c. 8th century BC] Oops. That's about as "un-virginal" as you can get, folks.

Here's another booger, as Pausanias describes the birth of the demigod (not God) Attis. Pikachu though forgets all the good stuff: Zeus was running around looking for ways to get his jollies and saw Mt. Agdus, which looked liked the goddess Rhea. In the ensuing fracas, Zeus drops some of his seed on the mountain, and from this arises a wild and androgynous creature named Agdistis. The gods don't like the obnoxious Agdistis, so Dionysus sneaks up and puts wine in Aggy's water to put him to sleep. While Aggy is asleep, Dionysus ties a rope around Aggy's gentials, ties the other end of the rope to a tree, yells "Boo!" and -- well, you can take it from there. From the resulting blood, a pomegranate (or almond) tree springs up, and much later, Nana happens by, picks some of the fruit, and:

a daughter of the river Sangarius, they say, took of the fruit and laid it in her bosom, when it at once disappeared, but she was with child. A boy was born, and exposed, but was tended by a he-goat. [Pausanias, Description of Greece 7.17.9-11] Dagnab. Insemination by fruit. Couldn't get any less "virgin" than that.

Having finished calling the ancients stupid, Pikachu's poor conscience closes with the question, "Can we morally say: "Ours is history, yours is a lie"? Of course we can. By the normal canons of epistemic history, it's always possible to look at evidence and decide that one story has a better chance of being true than another. Obviously there is no physical evidence left for the virgin birth -- anyone will admit that -- but here, the broader program of, "Did someone named Jesus walk the earth?" "Did he do miracles?" "Did he start a movement whose origins need to be explained?" -- enter the picture, whereas with Dionysius, Attis, etc. the problems are much more serious -- in terms of sources that are far too late, far too inconsistent, and incompatible with other records of history.

Pikachu has left himself be brainwashed by the politically correct whinges of John Dominic Crossan, who is so concerned about offending anyone that he doesn't even want to make a decision. His words, with our comments:

Augustus came from a miraculous conception by the divine and human conjunction of [the God] Apollo and [his mother] Atia. How does the historian respond to that story? Are there any who take it literally? (Precisely a point. Is Apollo referred to in any historical records of his contemporaries, like Tacitus refers to Jesus?)... That divergence raises an ethical problem for me. Either all such divine conceptions, from Alexander to Augusts and from the Christ to the Buddha, should be accepted literally and miraculously or all of them should be accepted metaphorically and theologically. (Now that's just plain stupid. There are also matters of genre and of historical setting; there's no "either-or" from just a list of names spat out uncritically.) It is not morally acceptable to say...our story is truth but yours is myth; ours is history but yours is a lie. (Of course it is. Just as it is "morally acceptable" to say that "the Holocaust happened" is truth, and "it didn't happen" is a falsehood. It depends where the evidence leads. This is nonsense.) It is even less morally acceptable to say that indirectly and covertly by manufacturing defensive or protective strategies that apply only to one's own story. (Well, isn't that just too bad. Appeal to evidence -- late documents; enormously inconsistent accounts (like 3-4 versions of Dionysus' origins), isn't a "defensive or protective strategy"; it is just the way it is. Crossan spends valuable time making excuses for avoiding the evidence that he needs to spend evaluating it.)[John Crosssan, The Birth of Christianity, 1998, pg 28 - 29.]