What goes on in Vegas most certainly will NOT stay in Vegas here!
Watch it go down (below)!!!
Too much romance for you, Chris??? We're sure RiRi understands!
The BFFs raced and joked around as they zipped through the island's streets.
He looks mighty happy! We wonder if he chowed down on some of leftover marijuana birthday cake??! LOLz.
[Image via FameFlynet Pictures.]