^Oh I'm aware that there was no sexual act commited (which really makes a line in the original F/SN visual novel very questionable). That's why I said poor Guinevere. Got no real husband, wasn't loved, had to raise a baby that she didn't even conceive. I'd still say that it's magic more than science, but sometimes the two are hard to tell apart.
I'm ruining this, but all I can think about is (horror movie spoiler alert): Eli: "Here, take this key. You're our last hope."
...Many year later, Umi is found hunging off of one of the castle/convent's windows...
@BugDevil: Actually, I believe that Morgan was the one who raised Mordred. Artoria and Guinevere never met Modred until she joined the Knights of the Round Table as a teenager.