"Periods? Oh no, we don't have those here."
"What do you mean you don't have them? You can't just not have them!"
"Well, we have them, we just send them away."
"SEND THEM AWAY? HOW? TO WHERE?"
"Settle down, it's very straightforward. When someone starts getting their period they go to the local witch or wizard or necromancer or whatever's nearby and get a spell placed on them. All the blood gets sent straight to the throne of the Blood King. Which is nice because he loves blood and isn't too picky about where it comes from. This way he's not running around starting wars for his blood. He gets it free and on a regular basis."
"But what about period cramps?"
"Oh, we send those away too. Off to the orcs of the Screaming Mountains."
"That seems like it could cause problems. Aren't you worried they'll retaliate?"
"Well, no. The orcs....kind of like it? They apparently like pain about as much as the Blood King likes blood. So as long as we keep sending the period cramps, they leave us be."
"huh, I wonder why more kingdoms haven't tried this."
"Probably because those other kingdoms have normal neighbors."