"It seems like you've had a lot of face-to-face opportunities with vampires in your life recently," Joan pondered after Leonard Ethan finished speaking. "You always end up finding mysterious things and places related to vampires."
"That's mainly because I've been active in Eastern Europe lately." Leonard Ethan explained as Joan's voice trailed off. "And as vampire legends originated from this region, there are more related historical ruins."
The earliest vampire legends date back to the 14th Century when Europe was hit by a widespread plague. To avoid contagion, people often hastily buried the sick without carefully identifying if they were truly dead.
For some reason, if people opened graves, they would find that the corpse had shifted position and was stained with blood. This was simply a result of the people not actually being dead when they were buried, and the struggles they made after regaining consciousness inside their coffins.