Larsa Pippen, Marcus Jordan Seal Secret Handshake With Kiss

Things are clearly getting quite serious between Larsa Pippen and Marcus Jordan -- the two now have a secret handshake ... one that they seal with a big smooch!!

Michael Jordan's offspring shared a vid of the couple's new intimate finger-locking greeting on his social media page Sunday night -- showing further that he and Scottie Pippen's ex are, in fact, an item.

In the clip, you can see Marcus and Larsa slapping hands repeatedly -- before Marcus, as part of the shake, put his arm over her head and pulled her in to give her a kiss.

It's a cute and romantic moment for the two -- but it also shows things have certainly progressed to perhaps official relationship status for the couple.

You'll recall, despite getting very close over the past few months, the duo has insisted they're nothing more than just good friends. But they've now each posted each other on their social media pages in the last few days -- with Larsa sharing a snap last week of the two holding hands in front of a Jordan floral arrangement.

For what it's worth, Marcus captioned his handshake video with the words, "Twistin’ up my fingers for my twin" -- something that sure seems to indicate things are heating up.