Markus Boehm is the wealthy German investor who owns Castle Finster, as well as three other houses.
Although Markus hires Nancy to investigate the latest monster sightings at Castle Finster in 2011, it's clear he doesn't really care about the place. He only cares about the Monster sightings because he has other potential investors coming over to see the castle. In her investigation, Nancy finds out that he used to date the castle's castellan, Anja Mittelmeier, and that the breakup was not a pleasant one. Even so, he believes that she does good work and that they are well past the relationship.
However, Anja credits herself for making Markus the successful person he is and wants to see him ruined for turning his back on her when he landed his first big deal. Planning to do so by dressing up as the Monster and staging various attacks that would have eventually culminated in the death of a young woman (Nancy), Anja would have made it look like Markus had set the whole thing up as a publicity stunt gone wrong by using emails she had written and printed in his name. After Anja is arrested, a shocked Markus sells the castle, believing its tragic history has become a bit too personal.
- "Wow. I do not care about that problem."
- "WHO TAUGHT YOU HOW TO DRIVE? WAS IT THE STUPIDEST DOG ON THE EARTH? BECAUSE THAT IS WHAT IT LOOKS LIKE! I tell you, Nancy, people have no manners these days."
- "A good vacation ends with you looking at your house and promising it that you will never leave it again."
- "They're stupid rich. Like, "happy birthday, I got you that town you wanted in France" rich."
- "It is so far out of the realm of possibility that it has crossed the sea of you are wrong and landed in the realm of ludicrous accusations!"