House Listing Attracts Attention Because Of Bizarre Buyer Requirement

Some houses have a strange history that makes them hard to sell- especially if the realtor is honest about the strangeness in their listing.This house in Cayce, South Carolina is being sold for a mere $155k, but it comes with one really odd catch- the buyer can't ask about the person in the attic.
The original Zillow listing was edited because of the unwanted attention it received online, but here's how it originally read:

Please read carefully before scheduling showings. May not qualify for financing. Great "diamond in the rough" investment property or primary home needing separate apartments. Little is known about condition except that property has active roof leaks. Property is being sold "as-is" with no repairs, no clean-up, and no warranties expressed or implied. Upstairs apartment cannot be shown under any circumstances. Buyer assumes responsibility for the month-to-month tenancy in the upstairs apartment. Occupant has never paid, and no security deposit is being held, but there is a lease in place. (Yes, it does not make sense, please don't bother asking.)

UPI dug a bit further and found a different listing that stated "Upstairs apartment is occupied by professional artist", which makes a bit more sense than "please don't bother asking".But who in their right mind is going to buy a house with a creepy tenant lurking in the attic?