Yes, it's a golden opportunity

You look around but you and Heather are pretty deep in the rocks. The people on the main part of the beach are about the size of ants, and they're looking at the beautiful ocean, not off into the rocks.

You aim your cock and start pissing right on Heather's back. You know it's disrespectful, but something about peeing on a girl feels amazing. It's total domination and humiliation, you're urinating on her skin. You watch as the golden stream splashes on her back, wiping away the cheap magic marker writing. You aim your cock to pee all over her back and she squats and allows it. You wonder about peeing elsewhere on her body, on her tits, her pussy... in her mouth.

But for now you stay try to the plan and "just" piss on Heather's back. You groan in enjoyment as you give her a golden shower. The nasty urine splashes down her bronze skin to her butt then onto the rocks.

Finally, your bladder is empty. You could just laugh, call her a nasty slut and leave her here. Most guys would.

"Come on, let's get back to town," you say.