Bella Thorne's Ex-BF Selling Her Crap Was a Joke ... But Really, She Owes Me $$$

6/13/2019 12:40 AM PDT

Mod Sun Says Bella Thorne Owes Him Money, Talks eBay Joke

EXCLUSIVE

Mod Sun has some unanswered questions about Bella Thorne -- the first being, why can't she take a joke? The second being ... WHERE'S MY MONEY?!?!

We got Mod Sun as he was leaving The Nice Guy in WeHo, and had to ask him about what he said a couple of weeks ago. ICYMI ... he told our friends over at TooFab that Bella's stuff was still at his place -- dubbed the Mod Sun storage unit -- and threatened to hawk it all on eBay.

Bella, of course, didn't take too kindly to this ... and blasted Mod as a fame whore.

Mod strongly hints Bella's stuff is STILL at his place, but he also says his issues with her go beyond that. We're talking finances, and specifically ... debt!!! He claims she owes him some cold hard cash, and it sounds like the already bad breakup could get way worse. 

As we reported ... Mod and Bella ended their 18-month fairy tale romance after their weekend in Coachella back in April -- and when she tried to get her stuff from his place, the ugliness began.