'Kardashians' Star is Rooting for Khloe & Odell ... 'They'd Be a Hot Couple!

Khloe Kardashian should reconsider the whole 'not officially dating' Odell Beckham Jr. thing -- so says one of her "Keeping Up with the Kardashians" co-stars ... who says they'd be a damn good couple.

We spoke with Jonathan Cheban -- one of Kim's closest friends -- who says he's heard the buzz about Khloe and the NFL superstar ... and says he really hopes they hook up.

"That would be a hot couple."

Khloe has downplayed the relationship ... saying she was just doing some boozy flirting with OBJ at Drake's party over the weekend.