X Factor finalist Charlie of MK1 tweets racy topless photo... while wearing Mr. Men undies

--> She's the tomboy singer with the angel face. But underneath her street tough exterior it seems X Factor finalist - MK1 singer Charlotte 'Charlie' Rundle has a more racy side.

The 19-year-old singer shared a topless photo of herself on her Instagram social networking site, dressed just in a pair of cartoon Mr.Men knickers to promote her former career as a DJ.

With her platinum blonde crop, and a pair of headphones it's certain to have attracted plenty of bookings for the young singer/rapper and please her new fans.

She tweeted: 'he promo shot for my old DJ sets ... Minus the Mr. Men'.

Charlotte is part of duo MK1, along with bandmate and best friend Simeon Dixon, 24 - from London.

Mentor Louis sang the group's praises after putting them through to the final: 'They are so current and relevant to today’s charts and Charlie has an amazing, original and brilliant voice.'

Their chances on the competition remain slim though against stronger performers such as Jade Ellis, Ella Henderson and Jahmene.

Head judge Gary was less than impressed with MK1's performance of the Jackson Five's I Want You Back, dubbing it a bit 'Glee'.

He said: 'Good energy, good visuals. vocals a little bit weak. It's a little bit Glee this week. Don't let Louis have too much input into what you sing.'

While Nicole had a mixed response: 'Sorry guys I didn't feel it this week. I think you guys were a little bit out of your element. The rapping was good.'

When asked why they think they should win Charlie said: 'The thought of being the first two piece to win is really exciting. We’re a niche band as well which should hopefully work in our current market.'