Rihanna's a sex kitten, and if you don't believe us, just look at her shirt.

We pretty much already knew Rihanna was a sex kitten (remember when she tweeted out a topless photo from the set of her "Where Have You Been" video? Or how about that time she allowed fans to see a bevy of scantily-clad Hawaiian vacation pics? Or maybe the time she posed nearly naked on the cover of Esquire? And then the time she dubbed her fragrance "Nude?") Anyway, if we weren't sure before, we definitely are now.

While out to dinner in Santa Monica, L.A., the five-time VMA nominated singer was spotted sporting a t-shirt with the slogan "Sex Kittens" plastered on the front (which came paired with a vaguely frightening "don't eff with me" look.) The shirt even had a couple of sexy cats on it -- just in case the "Sex Kittens" part wasn't self-explanatory. We normally wouldn't advocate for anyone to go around bragging about their sex life and / or relating sex with cats, but then again, it's RIHANNA. She's an IRL queen who can wear whatever she pleases.

Photo credit: Pacific Coast News