The Geordie Shore star is one of three celebs currently in the house
in a desperate bid to increase ratings for a new twist.
Marnie and fellow former CBB housemates Nicola McLean and Gemma Collins have joined the show and yesterday was their final night.
And it seems as though things heated up between Nicola and Kieran as they shared quite the passionate kiss.
"I'm already planning my wedding," sighed Marnie after the pair locked lips.
Ellie Young encouraged: "He's so nice."
Marnie told the girls: "He's the guy I should go for. I usually date guys who are cocky, forward and they'll just grab you but they're the worst type of boy."
Nicola asked of the kiss: "Was it tongues and everything?"
"Yeah," smiled Marnie, "It's the best Kiss I've had all year. Better kiss than [Marnie's ex] Lewis [Bloor]. 100%. I want to do it again."
However she ruled out taking it further in the house: "I'm not going to try it on with him."
The kiss follows Marnie previously ruling out kissing Kieran because of his history with follow housemate Rebecca Jane.
In the Diary Room together, the new celeb guests spoke to Big Brother earlier in the week about their first impressions of the housemates.
Gemma declared: "Marnie fancies Kieran!"
Marnie blushed: "I don't fancy him... I just think he's easy on the eye. I'd snog him but I feel that girl's [Rebecca] really hung up on him and I couldn't do that."
Big Brother 2017 continues nightly on Channel 5 with the latest episode tonight at 9PM.