Joanna Krupa & Boyfriend -- The Hot, Wet Bikini Hook-Up

Ridiculously sexy "Real Housewives of Miami" star Joanna Krupa got the ride of her life ... by straddling her very lucky fiancé Romain Zago in the nippy waters off South Beach this weekend.

The 33-year-old smokin' hot bombshell showed off her perfect Polish lady parts in an environmentally friendly green bikini.

Joanna is really wrapped up in her man.