so they are not blood related at all however on paper they are step siblings.
a korean woman transmigrated/reincarnate into fl's body. so yes she is from a different world however it isn't her body.
SPOILER
I once saw a comment that they actually aren’t blood related and Yus has never thought of her as his sister. That’s why he acts the way he does since he is the only one that knows she’s not blood related. Hope this helps :)
Oh thx so much I was getting worried cause I didn't want to support them if it was an incestuous relationship.
Actually, everyone knows they AREN'T blood-related. It's the reason why people don't really expect their relationship to be good, especially with the position of the Duchy's Head on the line. Not like it's much of a spoiler, really. She always says he's her brother tho, so it does feel like a weird reminder from time-to-time.
Can someone tell me if this is incest or not because isn't she from another world but she is in the half sisters body so that's still incest right?