They are not siblings so it's not that big deal.
Bro my brain can't take that. Wait what if one of them is actually adopted or illegitimate child? But that's still incest tho. OH MY GOOOODDDDD (;´༎ٹ༎`)(;´༎ٹ༎`)
It's not like they knew...
What if the fl was adopted and the royal blood? And her sister isn’t?
Nah not really since they are like 5th cousin and can be classified as strangers
If you want spoilers read this thread:
http://www.mangago.zone/home/mangatopic/11833919/
wait if the fl is of royal blood then... wouldn't that mean her sister is too? and if both jonas and her sister were of royal blood then... wouldn't that be incest even if the fl's grandmother was just the princess' cousin because they still are related