1 Book Found

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"A novel about a male teenager set in the United States of the 60s or 70s. It is a very satirical book about the lifestyle of that time and full of sex, drugs and Rock'n roll. Written by an US-American author. I read the book around the years 2000 - 2005, so it was probably published between 1998 - 2005. What details I remember are: 1) he is in love with a girl called Nina, 2) to get her attention he has to solve several problems throughout the story and every solution to a problem ends in an even bigger problem etc, 3) the mother of his best friend is sexually interested in him, 4) there is a church mentioned, something like "Kirche der großen barbusigen Jungfrauen" (I read the book in German), 5) drugs like Quaaludes are mentioned, 6) after school he works in a radio station (probably as a goofer or so), 7) when he finally gets the interest of Nina he is dissapointed as she doesn't have the sexual experience like the mother of his best friend has once in the radio station a female promoter of a record company confuses him with an important employee of the radio station and wants to give him a blow job (so he would play their records)"