Keith, egged on by Spice Girl Mel B, can be seen asking the presenter: "Holly, have you ever experimented?" To which the bubbly blonde replied: "No!"
Confused by the line of questioning, fellow Juice star Paddy McGuinness asks: "What do you mean, experiment? What are you on about?"
I… Mel! No, no… like what do you mean? No!
Clearing things up, risqué Keith confirms: "Well, getting off with your own sex."
"No, no, no I haven't," Holly added, but Keith continues: "Have you ever kissed the sweet lips of a lady?"
"What are you getting at?" Holly asks, "No!"
Clearly worried, guest Stacey Solomon pipes up to ask: "Is this going to be a game?"
But the real fun started when Mel B branded Holly a liar.
Mel – who recently revealed she had an fling with Geri Horner in the early days of the Spice Girls – says to Holly: "Don't lie."
Clearly squirming, Holly stumbled over her words and said: "I… Mel! No, no… like what do you mean? No!"
A disbelieving Mel laughs and comments: "Your voice has gone really high."
Winking to the camera, as a giggling Holly put her head in her hands, Keith quipps: "I think Holly has answered the question there."
Catch all the Celebrity Juice action on ITV2 tonight at 10pm, with Joe Swash, Marvin Humes and Susanna Reid also joining in the riotous fun.
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