" Yeah, you bet Romani.' Percy bared his forearm and showed them the brand he'd got at Camp Jupiter- the SPQR mark, with the trident of Neptune. 'You mix Greek and Roman, and you know what you get? You get BAM!'
He stomped his foot, and the empousai scrambled back. One fell off the boulder where she'd been perched. "

― Rick Riordan , The House of Hades (The Heroes of Olympus, #4)