Chantelle, who won CBB in 2006, and 2007 contestant Chanelle were among thousands of people who took to Twitter to express their disbelief after half of the current housemates were shut in an Over 18s room.
Lee Ryan, Luisa Zissman, Sam Faiers, Jasmine Waltz, Ollie Locke and Lionel Blair were all dressed in black PVC bondage gear and used vile language as they grinded up against each other for the challenge.
Watching from home, Chantelle tweeted: "WTF has happened to Big Brother??? Is this actually happening? #CBB."
Chanelle, meanwhile, told her followers: "OMG this is really weird #cbb." Messaging Chantelle, she asked her: "@chanellejhayes what are we watchinggggggggg?"
Is this actually happening? #CBB— chantelle houghton (@chantellehought) January 12, 2014
The stars were by no means the only ones to comment on last night's show either.
One viewer tweeted: "'Celebrity' Big Brother is turning into a continuous porno... #awks." Another admitted: "Rather disturbed with Celebrity Big Brother tonight!"
However, other viewers enjoyed it: "Celebrity Big Brother is soooo good this year," one female tweeted.
A guy added: "Did anyone else just love the kinky bondage twist on Celebrity Big Brother? I found it very entertaining. To say the least lol. #CBB."
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