Book title needed (From 1980s)?

I am looking for a book from the 1980s-- it was horror fiction. The only things that I can remember is a man who did tarot readings who did one for someone and it came up that the person was going to die. After the person left, he couldn't believe what the cards said (because he always manipulated them into what he wanted to say for the client). He started did a reading for himself and it was death.

The other part was about this young woman who was pretty loosey-goosey for the time and she had a different guy every night..... and she picked up this guy who ended up to be the killer-but he was like a paranormal killer because they were having sex and the author describes her as having really good sex and an incredible orgasm that didn't stop.The woman couldn't feel her legs it was so strong and eventually (too late for her) she figured out that the killer was eating her (but in the sense of making her dissappear) and it was like one long delicious orgasm to her. Help is appreciated.