The pair are said to have been ‘secretly dating’ since meeting at the studios earlier in the series.
And despite the pink-haired lady previously being linked to cheeky Harry Styles, it seems blonde cutie Niall is the One Direction boy with all the charm as he won Amelia’s affections.
The couple met when last year’s X Factor boyband teamed up with 2008 runners-up JLS and the X Factor finalists on charity single Wishing On A Star and are now said to ‘like each other a lot.’
A source told the Daily Mirror: ‘Niall and Amelia met backstage after One Direction performed on the show.
‘Although Harry spent most time with her, it was Niall whose eye she caught. Niall can be pretty shy but he made his feelings clear.
‘After swapping numbers, they were texting all week and met up on a secret date in London where they kissed for the first time.’
Niall failed to keep his affections for the 17-year-old rock chick hidden as he tweeted his support for her during Saturday night’s semi-final show.
‘round one goes to miss amelia lily for me! cmon little mix ,not a disaster they will kill it next song! they lookin good tonight,’ he wrote before adding: ‘little mix and amelia deffinate finalists! love them.’
But the source added that Amelia has been trying to keep her head down and make sure their romance remains a secret.
The One Direction boys certainly seem to be fond of having X Factor arm candy given that Harry is apparently dating Xtra Factor host Caroline Flack, 15-years his senior at 32, and Zayn Malik was last week linked to Little Mix’s Perrie Edwards.
Niall is keen to get the three couples out on a triple date as well.
The source added: ‘With things getting serious between Harry and Caroline – they are always running off to grab five minutes over the phone and secretly arranging to meet up – Niall has been joking about them all triple-dating, along with Perrie and Zayn.’