I'm not really sure specifically about 'ppgz y rrbz vampiros fanfiction' as it seems quite a niche combination. But you could start by looking on popular fanfiction platforms like Archive of Our Own or FanFiction.net. Try searching for the key words and see what pops up.
You can try looking on Wattpad. It has a wide range of fanfictions, and there's a chance you'll find something related to 'ppgz y rrbz vampiros' there.
The main distinction of porn with a story genre from regular porn is the presence of a coherent narrative. Regular porn often jumps straight to the sexual action, while the story genre tries to add some kind of story framework around it. But in the end, both are adult-oriented and feature explicit sexual content.
Well, it's hard to say for sure. The concept of 'porn-like' is quite subjective. Some might consider certain novels with excessive sexual descriptions as such, but it depends on individual perspectives and cultural standards.
In many places, 18+ porn comics are considered illegal. This is because they can have a negative impact on society and violate moral and legal standards.