I think seduction manuals are morally wrong.
What you think isn't interesting, but I would like to see a comprehensive, well formulated argument as to why you think that; indeed I have commented extensively in this thread to find such an argument, but mostly its that all the other arguments just shame language (rape culture, you have a problem. I will be sincerely please if you could provide a good argument against my position.
Morality is a very complex topic that possibly can't be proven by logic anyway. Why is racism immoral, other than the fact that we, as a society, have decided that it's immoral?
I think seduction manuals are immoral because they essentially treat women like min-maxers do video games--do this, and your chance of success is raised by X%, follow this procedure to succeed, etc. It makes women into vending machines that, if the buttons are properly pressed in the right succession, will theoretically result in a prize--sex--being dispensed. I think that treating people like that is immoral. Can I prove this logically? Can I claim that this is a universal truth? Of course not, but the same is true for every moral stance.
Think of the difference between a book on the history of racism, with very explicit quotes, long, in dept conversations with racists, scientists and policy makers, the authors own experience in these groups, etc and the latest publication from the KKK.
A seduction guide is the first. "Rapists Quarterly" is the second.
Also nicely done working an adhomium in there.