Books like this exist because most men are not "naturals" with women. On the surface it will seem creepy and calculating, but pickup artists are just doing what guys with natural game (charisma/charm/etc) do automatically. With enough practice any man can become a "natural". Some people can pick up a musical instrument and just play with no training or instruction. Others need to practice for years. It is really no different.
If you are looking for relationship management, this is not the best book. For meeting, picking up women, and getting laid, it is a great place to start. The fundamentals and psychology behind why pick-up works are needed in relationships, but it is a very deep rabbit hole to travel down. I am talking red/blue pill "Matrix" type expansion of your mind and beliefs.
If all you take from the book are tricks/techniques that can be used to manipulate women, you are missing the whole point. Women are very good at identifying fakes and phonies. Much better than men by a wide margin. If you put on an act, you may get some short term success (one night stands, phone numbers, a date or two), but you won't keep a girl around long once she figures out it is an act.
The real "truth" in the book is to be confident and outcome independent. You don't need tricks to do this. You simply need to realize that talking to a girl will have 1 of 3 results.
1. She is into you and continues the conversation.
2. She is neutral/shy and will give you short polite answers (waiting for you to leave or to impress her enough to be #1).
3. She will be rude and blow you off.
Being outcome independent means accepting the result you get without letting it get to you or attaching too much meaning to it.
Most men do not have enough confidence to even talk to a woman they find attractive. A book won't give you or them this confidence. Only talking to every woman you find attractive until it becomes "natural" does.