Hallo Dear, by ”hard fanfic” I'm assuming you mean Smut, yes I do write smut from vanilla to noncon, I'm grey ace meaning I experience limited sexual attraction and while yes at some point I want to be in a relationship maybe later in life a mum, some of the stuff I write I wouldn't want to do it with my future partner.
I do read Smut but do I get turned on by it? I hardly do, acexuality it's a big umbrella not all aces are the same some of us are sex-repulsed others no it all depends on the individual.