Self Flagellation. Reasons and How to achieve?

After a little of browsing and information collection, I found that there are quite a lot of reasons why people self flagellate. Whether it be for religious reasons or for redemption, it struck to me as quite intriguing and a matter to dig deep in. Then I came across an article :

https://www.salon.com/2013/03/17/my_tantric_awakening_turned_me_off_sex/

After reading this article for 3 times, I felt even more fascinated. Like "Wow, that's the shit right there. I seriously wanna try that.", but then I tried searching it on the web and couldn't find any books or useful info.

I honestly don't know how many different ways there can be that someone can self-flagellate but I really do wanna know about it. Can you share your thoughts and intel on Self-Flagellation, Pain and Pleasure, whipping.!!!!!