If there’s one thing Rihanna probably knows, it’s her second-tier ’80s hair metal bands, amirite? Perhaps not, but that didn’t stop her from rocking a Krokus shirt at the kickoff of the Monster Tour with Eminem. If you’ll remember, she’s made some metal-themed sartorial choices before, like the jacket she wore that popped up on Chris Brown a few weeks later. We’re guessing it’s a styling assistant of hers that likes metal, or at least has an appreciation for buying old shirts for hundreds of dollars. At least Lady Gaga genuinely enjoys the artists whose shirts she rocks, which you can tell by her hanging out with them. But hey, perhaps Rihanna’s shirt might make some Eminem and Ri Ri fans dig back into the Swiss band’s rich heritage and discover – ah, we can’t even say it with a straight face.