I got it in my head that it's a sort of red 
    pilled book that teaches you how to manipulate 
    people. 

You're not totally wrong. It's been ages since I read it, but there are parts that feel a little transactional but also many that don't, and it never advocates dishonesty or exploitative behavior or anything like that.

(I also view the ability to influence people as independent from morality. It's like learning MMA or hacking or something. They're not inherently "good" or "bad" skills - your morality determines how you'll use them)

Ultimately I think it's great and I recommend it. It's certainly cheap enough! I'm sure there are a zillion copies on eBay for like two bucks.