oops I meant to post text with this, but I won't be able to find the image again...
Do you think a heart looks like an upside-down butt or does a butt look like an upside-down heart? How did butts become romantic?
Butts are romantic because they show someone has a lotta nutrients, but also because they're nice to the touch.
A fictional heart is most definitely an upside-down butt, throughout history people were keenly aware of how real hearts looked.
No such thing, similarly to how an E has no connection to a ヨ. Personally, the heart symbol reminds me of lungs, or angel wings, the motif of impossibility of flying and ascending from human responsibilities.
Are you sure? I'm pretty sure people's organs weren't a mystery back in ancient times...