Simon joined Louis and his former girlfriend for an evening at private members haunt LouLou's and they all looked in high sprits as they left.
It was recently confirmed that, Louis would be returning to The X Factor, along with Gary Barlow, Nicole Scherzinger and new/old judge Sharon Osbourne.
Perhaps Louis wanted to buy Simon a drink to say thank you for keeping him on the show...again!
Despite living in the US now, Simon is back in the UK for the final of Britain's Got Talent, which will air on ITV1 this weekend.
Never one to miss an opportunity to hang out with her ex-flame, we're guessing Sinitta couldn't wait to get on her dancing shoes for a night out with him!
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