Rihanna, Rihanna, Rihanna! We know you're a wild girl, but showing your nipples in public isn't just Rated R like your last album -- it's straight up XXX!

The 24-year-old R&B songbird went out in New York City last night, and it sounds like she had a blast hitting the club scene with her girls. Not only was she showing off her tatas in a sheer black sweater, but she was posting tweets like, "Hey b*tch, hey b*tch, hey ho!" and "A$$ so phat I need a lap dance!!!!" Sounds like someone had a good time!