Incest? With whom? I mean I could possibly imagine, but then this Story would be a fixed event, and everything that will happen, already has. Assuming were talking about being the Twins Dad. Which even I'm starting to suspect, might be the case. Thing is, this Story seems to be in a first phase shift. So how were the Twins actually there, at the start then?
Better question, what are the chances that you end up being your own Dad? 'cause that to me (At the moment), is feeling just as likely.
Otherwise I was under the impression that the MC, was an orphaned only child, with no Blood relative's, so Incest?! like I mentioned not sure I'm seeing it.