In a recent interview Rihanna said the reason she's always on Twitter is because she never gets any booty calls...
From The Ellen Degeneres Show
Rihanna: "I like men that are more aggressive but mysterious but I like a man to be very sure. I like them to be sure of themselves and know that you're the man. I'm the lady and the only way for us to make this work is for us to play our roles. You know, I can't really be the man for you. I don't want to have to be. I'm the man at work all the time."
Ellen: "I think especially for a powerful woman and you make a lot of decisions the whole day. Your job is to make decisions. You want somebody else to take control and make those decisions in a relationship. And that's hard to find a guy who's not going to be intimated by the power you have. And, realize there's got to be another side."
Rihanna: "Definitely. It can be difficult but I think really right now, I'm not giving the time. I don't have the time. I'm not necessarily happy being single. It's not really that cool."
Ellen: "But you're OK with it?"
Rihanna: "It sucks but it is, what it is. Let me say this right, because I don't want to make it seem like, my work is my everything. I do put a lot into my job. Most of my time if not all of it. It definitely affects my personal life. My personal life is pretty much non-existent. Which is not good, not for the long run. Not for me, not for "her" [points to in-between her legs] It's not fun." [laughs]
Ellen: [laughs]
Rihanna: "That's why I stay on Twitter a lot. So I can conversate with my fans. Because I don't get any booty calls."