Camille Grammer sure is affectionate.

When the 42-year-old Real Housewives of Beverly Hills star invited a group of friends over for a game of tennis, her costars were stunned when Grammer planted a wet one on her platonic pal Nick -- as his wife Tricia looked on in disbelief!

"The whole kissing someone else's husband on the lips is just bizarre," Kyle Richards says. "I can tell you that if Camille were to kiss my husband on the lips, she wouldn't have any lips left!"

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The Real Housewives of Beverly Hills airs Thursday at 10 p.m. (EST) on Bravo.