You don't have to be blood related to be in an incest type of relationship. If you are siblings, blood related or nah and in a relationship, thats incest (=・ω・=) I hope that answers your question. In irl incest stuff is actually really harmful to human psychology for a few reasons you can go ahead and research about the topic if you are interested but since it is fiction it is ok I guess? It still weirds me out but yea
Oh I have heard about how incest fucked up genetics like those in royalties back then. That's why I'm wondering if it needs to be blood-related to be REALLY considered as incest, not just by the labeled relationship. And you answered my question, thank you so much. ^^
I'm really wondering what can be considered as incest. Does incest have categories like blood-related incest and relationship incest (step siblings)? Or it just depends on how the reader perceive it? /gen