there's a traditional Korean legend about how the Park clan hatched out of a golden egg and in ATEEZ Seonghwa is the only Park in the group hence him coming out of a golden egg
It's perfectly normal and fine to be attracted to different things (as long as no one is harmed, of course) :) Personally, I'm asexual, so I'm not affected by San's chest beyond simply being impressed by all the hard work he's put in to get into such great shape! The man is a work of art