The Battlefield Casanova

Shisui, an 18-year-old player, was under the impression he was playing a new fantasy RPG entitled Everlusting Life. Little does he realize, however, he gets pulled into the game universe itself eye-to-eye with the world's goddess, the goddess Etarnitas. Here's her single divine directive?
"Impregnate my eleven virgin daughters and save the realm."

What could go wrong? (Spoiler: everything.)