Rihanna and Rob Kardashian spent the entire day together this past Saturday (Aug 25).

First, they went go-karting in Burbank, CA, and then later that night, they were spotted smoking a blunt together at Playhouse nightclub in Hollywood, where they partied alongside folks like Lauren London, Sean Kingston and Chief Keef.

Chris Brown as also in the building, but sources tell E! News that he and Rihanna’s parties didn’t interact with each other … for obvious reasons.

Rihanna and Rob’s outing has sparked questions about whether or not the two are dating. They were rumored to have hooked up back in February, but haven’t been linked since … until now.

But it’s “not what you may think,” Necole Bitchie notes:

The two hit up Racer’s Edge Indoor Karting in Burbank Saturday with a group of friends to celebrate the birthday of a mutual friend, Capricorn Clark.

Rob is also currently dating Rihanna’s Roc Nation look-a-like labelmate Rita Ora … so things would definitely be a little weird if he was cheating on Rita with Rihanna.

[Pics: Necole Bitchie, BuzzFeed]