Coronation Street actress Michelle took to Twitter after half of the housemates dressed up in PVC outfits and acted lewdly for an '18-rated' task.
During the show, Lee Ryan was seen pole dancing in just a dog collar and pair of Y-fronts, while Sam Faiers whipped pensioner Lionel Blair's bottom.
The contestants were told to perform adult entertainment and none of them, including Lionel, refused. If anything, they all appeared to be enjoying it.
During the show, Michelle tweeted: "Lee... Ewwwwww ewwwww ewwwww!"
TOWIE's Lauren Pope added: "My eyes my eyes."
Lee.. Ewwwwww ewwwww ewwwww!— michelle keegan (@michkeegan) January 12, 2014
Dappy's N-Dubz bandmate Fazer couldn't believe what he was seeing: "Lee just bloody NO!! Ollie took the words out of my mouth, 'That is just bizarre'."
The reaction from some was that Lee's behaviour in particular made people "sick in their mouths".
The Saturdays' Rochelle Humes: "Lee just made me vom in my mouth."
Mario Falcone, who appeared on CBB's last series, also tweeted: "Think I was just sick in my mouth! Cheers Lee!"
judging by everyones tweets, i wasnt the only one that was a little bit sick in their mouth watching cbb last night!— Francesca Sandford (@FrankieTheSats) January 13, 2014
Catching up on the C5 show this morning, Rochelle's bandmate Frankie Sandford added: "Judging by everyone's tweets, I wasnt the only one that was a little bit sick in their mouth watching CBB last night!"
Meanwhile, former CBB winner Chantelle Houghton and BB contestant Chanelle Hayes have also spoken of their shock.
Our CBB blogger Nicola McLean described the task as "explicit" and an "embarrassing train wreck".
However, plenty of stars have spoken out in support of the task and Lee, including his Blue bandmates Antony Costa and Duncan James.
Antony said on ITV's Daybreak today: "As we all know it takes two to tango, it's not just all Lee. Lee's a good lad, I wouldn't be in a band with him for 14 years if he wasn't, so he's got a heart of gold. He's a good lad."
Elsewhere, TOWIE's Kirk Norcross, a former CBB housemate himself, tweeted: "#cbbuk #basicallyporn #BONDAGE #celebbigbrother best episode so far!!!!"
Other fans tweeted to say last night's naughty antics had only made them want to watch tonight's episode even more. "@bbuk was so fun last night cant wait to see what tonight has instore for us all #naught #CBB," tweeted one.
CBB continues tonight on Channel 5.
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