So, the other day I was re-reading some older fic and stumbled across Focus, which of course I have read but had forgotten about, and AHHHHH. Jensen with a nipple ring and Jared very into playing with it and lots of hot tenderness and...NRGH.
And then I read some newer fic and ran across thenyxie's A Ring for You, which features Sam and Dean, both with piercings (and bonus dirty talk!) and...AHHH.
I have come to this conclusion: There should be more piercing fic.