I remember reading this manga years ago now, but can't remember the title. It was edgy and definitely NSFW. I didn't get far into it because the subject matter was a bit too much for me at the time.

What I remember about is that the male-lead, who has a female childhood friend, who gets seduced by the female-lead who turns out to be a vampire or succubus or demon. I explicitly remember that I stopped reading because the childhood friend is mind controlled/seduced and raped by the female-leads familiar.

Hopefully that's enough to go off of.

This Holy Knight
I don't recommend this tho

Yeah I know my english is bad

That's it, thanks.

I needed to know because the title "Vampire Knight" was the first thing that came to mind, but that was definitely not the right title.