Ok, I was under the impression that Original Sin refers to the fall from god's grace of humanity when adam was tempted by the devil to rebel and taste the forbidden fruit. This is associated with the development of shame in nudity but I don't see how romance has anything to do with this at all.
Well....Adam, just like Eve, knew that they weren't supposed to touch the apples but they still decided they'd do it together. Adam did an incredibly stupid thing because his partner asked him to and he didn't argue very much against doing it.....when do people do incredibly dumb things for others? Hint: it happens everywhere every single day.
And after they both faced high punishment together they went on to make lots of babies.....soooo....yeah, romance is the key element in dumb decision number one.
