Rihanna, Chris Brown "Very Affectionate" at Grammys 2013 Afterparty

Chris Brown and Rihanna attend the 55th Annual GRAMMY Awards at STAPLES Center on February 10, 2013 in Los Angeles, California. Credit: Christopher Polk/Getty Images 

Rihanna and Chris Brown walked away empty-handed from the Grammy Awards at L.A.'s Staples Center on Sunday (Feb. 10) -- but the on-again couple still felt like total winners in one another's company. During the evening of lively performances, Brown, 23, noticeably failed to join the audience in numerous standing ovations for the likes of Carrie Underwood, Kelly Clarkson and his nemesis Frank Ocean.