Which type of aunt-nephew sex is creepier?

When you have sex with a person your own age (actually about a year younger) whom you did not know was your aunt, because you didn't meet until you were both adults, and neither one of you has ever met the father/brother who defines your biological relationship....

...Or when you have sex with the significantly older woman who was married to your uncle?

I wonder if that's why Tommen finally jumped out of the window? This show is absolutely un-rewatchable.