@
AlmondMagnum I'm pretty sure it's the second option since of all the girls only the vampire managed to get pregnant and she's old enough that the country she came from changed names in her lifetime. And if you stop to think, he asked god for a body that can't get sick so.. Yeah
EDIT: And I just remembered that in other mangas other races such as elves tend to be harder to ''impregnate'' (dunno if I'm using the right word, english's not my first language,
if somebody could correct me with a better suited word I'd be thankful)