Dampyr #105 (2008) pages 13-14: Hunted in the tunnels

The spok (ghost) of Gustav Meyrink leads Harlan through a tunnel to evade capture:

(Sonderling to Kurjak) “Who knows? It might not be necessary anyway. Alastor and Dagon are hunting your friend Dampyr.”

(Harlan) “I can't find the exit, Gustav. We're lost, but I can stop and face those two ugly mugs.”

“Forget it, Harlan. Your weapons are totally useless against two princes of hell.”

“Two princes, huh? So they sent two blue-blooded devils to capture me?”

“The worst of them.“

“I guess you have no idea how to get out of this dungeon.”

“Just so, unfortunately. Giacomo and I got here easily, being intangible spoks.”

“And you could just as easily leave. Go then, Banker Meyrink. Save yourself.”

“Without you? I could no longer face Nikolaus if I abandoned you, but I can try to stop them, delay their advance.”

“Oh, no! I cannot allow another of Nikolaus' friends to sacrifice himself for me. We will stay together at all costs. The wall is damp. The Moldau River must run behind these rocks. If only…”

“Harlan Draka! There they are!”

Gustav Meyrink was indeed a banker at one point, but he's better known as the most famous German fantasy writer of the early 20th century. He became an author after being jailed for embezzlement. His most famous work is the novel "The Golem," which set the standard for future stories about giant automatons like Mad Thinker's Awesome Android, or the Asgardian Destroyer.

Giacomo Casanova was an eighteenth century Italian celebrity known as a ladies' man and adventurer, basically one of the prototypes of the modern action hero.