This is like saying “should I stay friends with this person because I found out they like slasher movies and slasher movies are bad because violence and gore and murders are bad!!!!”
Honestly do whatever you want. But you can’t “police” how other people create their art, or what type of art they create, that’s not your business. Also fiction and dark fics aren’t a reflection of the artist’s moral compass.
Also this sorts of censorship and “writing fanfiction about taboo things makes you a bad person irl” mindset are lowkey fascist beliefs. So I think it’s a good thing that a talented and skilled writer isn’t, you know, a fascist.
Also also, AO3 (assuming the fic is on AO3) is literally a site for freaks lol. Giving a platform to dark fics about rape, incest and other fucked up things is literally the main reason the site was created in the first place. Because these types of fics were banned on other platforms, people came together and created a new site that was safe for all taboo fics. And surprise, that site is AO3.
So anon, if you don’t like dark fics, if you have a problem with it and have to check if an author is “pure enough”, then maybe AO3, a site created mainly for taboo fics, may not be a place for you, with all due respect.
This blog supports profic / proship / dark fics and is anti censorship by the way