The celebrity couple arrived arm-in-arm at the glittering bash.
After arriving in Rome on Monday the pair have hardly been seen outside their £1,000-a-night hotel suite.
But they looked very much a superstar item at swanky pre-show and post-show parties.
"I'm having an amazing time, I love Italy. But I'm trying not to eat too much because it makes me too sleepy," Naomi told.
Usher - who picked up the Best Male award and the Best Album award - was reportedly sporting a £100,000 gold chain around his neck.
British beauty Jamelia was not too impressed with the American singer's bling factor though.
"That's so stupid!" she said. "You should buy a house, rent it out and invest it."
The singer also laughed off rumours linking her with N*E*R*D star Pharrell Williams.
"He's drop-dead gorgeous but he just kept staring at me - it was really irritating," she said. "He's a nice guy, but ... I couldn't imagine seeing him."
