Louise and Niall were first linked together in May when she was dating her co-star Andy Jordan. As Louise's relationship with Andy fell apart, they often argued about another man, rumoured to be Niall.
Now, according to today's Sun On Sunday (1 December), Louise has stepped things up with Niall.
A source tells the newspaper that the pair have been enjoying a series of secret meetings at Niall's North London home.
They said: "Louise has been dating Niall - they've seen each other lots and talk all the time. But it suited both of them for their nights together to be secret. He'll sneak her into his house in North London, often when it's dark.
"She makes sure she doesn't do anything around Chelsea to try and keep the romance away from the prying eyes of her co-stars on the show."
Just weeks ago, uni student Louise was seen on the E4 reality show telling friends she wanted Andy back - despite Spencer Matthews claiming they'd spent the night together, which Louise strenuously denied.
She also recently posted pictures on Twitter of herself kissing Professor Green's friend, DJ IQ.
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Meanwhile, Niall was most recently linked to 16-year-old X Factor contestant, Tamera Foster.
However, in a recent interview, Niall insisted he was single.
Do you think Niall and Louise would make a good couple? Tell us below!
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