I’m going to assume this is about Thor/Loki being incest? Which, like, if it makes it easier for some people to come over and play in the Thorki corner of fandom, I’m hardly going to complain, I absolutely want more people playing over here!
But I think it’s weird ground to say that it’s not incest because they’re not biologically related, as it gets into territory where, “Oh, they’re not really brothers, because Loki was adopted!” And that’s not true at all, you know? They absolutely, absolutely are brothers–the movies themselves make this point very clear: They were raised together, they played together, they fought together. There is no question that they’re siblings.
And I get that the point of shipping them with this idea is, oh, well, they’re siblings, but it’s not incest because they’re not biologically related, but I think it gets into this weird place of denying what they are to each other, that adopted kids are 100% just as much a part of the family as biological kids, that in every single other way but biology, these are two siblings fucking.
This often comes with the whole, “But genetic defects in babies born to parents who are related!!” but, as I understand it, you need generations of inbreeding before that becomes a problem, it’s not an instant thing.
I also get that this argument is (or at least was?) often used to shut down the, “That is so gross, they’re brothers, you sicko!” insults that were thrown at Thorki shippers for a long time, it’s an easy way to put down that argument. But I think it ignores that they are brothers and that this is an incest pairing we’re shipping and, you know what? It’s fiction. It’s fine, we’re all fine here.
Nobody has to, if incest makes them uncomfortable. And I’m actually not going after people who follow the logic of “it’s not incest if they’re not biologically related!”, because, seriously, if you’re only here for Jotunn!Loki AU fics, well, we’ll get along just fine.
I see it as one of those things where it’s fine if that’s the logic you’re using for yourself, but trying to use it to convince others (which I’m not saying that that’s what you’re doing, btw, just that I’ve seen it used in such ways before!), I don’t think it holds water, because it’s like saying Loki isn’t really Thor’s brother or isn’t really Odin’s son or isn’t really Frigga’s son. And that’s bullshit, because he 100% is, no matter what that contrary little shit says. ♥