Meg Thee Stallion, Klay Thompson To Attend Jay-Z Event, Auctioning Performance

Two months after launching their relationship, Megan Thee Stallion and Klay Thompson are once again stepping out in public ... this time at a star-studded Jay-Z event!

TMZ Sports has learned Klay, 35, and Meg, 30, plan to hit up Hov and billionaire Michael Rubin's REFORM Alliance Casino Gala at the Ocean Casino Resort in Atlantic City on Saturday, one of their few public cameos together.

Of course, the future Hall of Famer first got people talking about him and Meg on July 12 ... when he posted a pic kissing a woman whose back was to the camera. Fans speculated it was the rapper.

Then, just a few days later, on July 15, Klay and Meg hit up NYC hot spot Carbone together, where they walked hand-in-hand.

It was no summer fling, either ... 'cause months later they're heading to the star-studded bash as a couple.

As for the event in AC, it's all for a great cause ... criminal justice reform, a cause near and dear to Jay and Michael's hearts.

Meg won't just be an attendee. She's auctioning off a private performance ... with proceeds going to REFORM.

We're told Megan wanted to return the favor to Jay-Z and Rubin ... who were very supportive of Meg's charity event, the Pete & Thomas Foundation Gala