graphic incest, pedophilia
This pornographic pulp novel is rare, and is not very well written. The plot seems to involve a combination between a super-scientist getting his own fortress paid for by the hidden underground of gay men in power, and another man who makes a deal with a devil.
The majority of the plot involves luring a gay couple into a secluded area and bringing them into an underground cavern containing a cult of young boys being raised by a scientific genius. However, part of the plot somehow centers around a demonic pact making one of the main character's son age before his eyes. Because they're both handsome and so much alike, they have lots of sex together. Somehow having sex together seals the demonic pact and causes the son to be demonic and the father's body to be possessed - though we haven't the faintest idea why this is important nor what anyone stands to gain from it.
Don't bother trying to track this down unless you are really a fanatic.