Instruct: Classify an Amazon review into positive or negative sentiment.
Query: This is NOT appropriate for the under-16 crowd

Rocket fuel for adolescent angst - great stuff if you're looking to push your teen boys towards the broody wasteland of Colombine.Overrated. A simple point about the potential consequences of time travel is explored, with great tedium...over...and over...and over.. again. The "surprise" ending of the book was transparent and obvious from the first page. The protagonist is completely socially isolated, completely caught up in himself (literally!), and living by no rules but his own. Homosexuality, incest, and orgies are front and center as themes in this paen to voyeurism and perversion. Easily identifiable as a creation from the "Me decade", where it deserves to stay.