Looks like there's trouble in paradise...

Blac Chyna was out and about running errands in her purple Lamborghini today, and she was practically begging us to notice that she wasn't wearing her diamond engagement ring from Rob Kardashian. The former stripper held her bauble-less finger in front of her face as she exited a parking garage, and all signs point to another ChyRo breakup! And after a pit stop, she met up with a mystery man for lunch -- is she trying to give Rob a nervous breakdown, or what?!

It's not that surprising, though, given that the video vixen was allegedly spotted getting a little too cozy with a mystery man at a Super Bowl party in LA. Rumors that she's been cheating on her sock designer fiance have been swirling ever since, so much so that his family has reportedly hired a P.I. to catch her in the act!

"Rob’s sisters have hired a private investigator to follow Chyna and catch her cheating," a source dished to Radar.

Unfortunately, it's a lose-lose situation, because they know if they find something their bro will be crushed.

"It is a double-edged sword. Rob’s sisters know that, if they catch Chyna cheating, it will break Rob’s heart! The last thing that anyone wants is for Rob to slip back into the dark depression he was in before meeting her," the source added.

We really hope they did split, so we never have to waste our time writing about this con-artist ever again!