Sheer madness! Rihanna turned up at Hollywood hotspot Eden on Thursday, Jan. 24 for a night out -- and just like her many, many snapshots on Twitter and Instagram, the 24-year-old superstar was completely comfortable revealing her world-famous body. This time, the "Diamonds" singer, with bright-red lipstick and wavy blonde hair and a tight, short little back dress made of completely sheer fabric.

PHOTOS: Rihanna's bikini body

Stepping into Eden (with the help of security guards), Rihanna was noticeably wearing skimpy black thong underwear and no bra. Prepping for a proper worldwide tour in support of her seventh studio album Unapologetic, Rihanna has had a relatively low-key January after stepping out multiple times with on-again boyfriend Chris Brown (the pair spent Christmas Day together at a basketball game).

PHOTOS: Rihanna and Chris' controversial romance

Among those not enthralled by Rihanna's reconciliation with Brown, who assaulted her almost exactly four years ago? Girls star and creator Lena Dunham. "She's talented. And then she gets back together with Chris Brown and posts a million pictures of them smoking marijuana together on a bed. And it cracks my heart in half in a way that makes me feel like I'm 95 years old," Dunham, 24, admitted in a recent interview.

For her part, Rihanna was definitely enjoying herself past midnight on Friday. "Eyyyy . . . must be da moneyyy!" she tweeted after her Eden outing.

This article originally appeared on Rihanna Exposes Breasts, Thong in Completely See-Through Dress