Can someone explain WHY THE FUCK I AM READING THIS???
Simple: because you are a horny degenerate, just like everyone else. Meanwhile, visual storytelling allows exploring such... eh, let's say "uncommon"... scenarios, without anyone even potentially getting hurt in the process. You'll find that there's media available for a wider choice of even rarer scenarios, some of them obviously hurtful for participants were they attempted in real life.
There's quite literally nothing to be ashamed of if you find yourself enjoying stuff like this, seeing as how such preferences are likely primarily caused neurologically, and no one chooses the way their central nervous system is wired.
After all, no one is hurt if you choose to read it. Actually, no one is hurt even if you find a partner willing to emulate it in real life, as long as it's all sane, safe and consensual.