"Billionaire Pierre Newman needs a fiancée--and fast! Frumpy, inexperienced Georgie is the complete opposite of the high-society women he usually has at his beck and call, but she will have to do! Their engagement charade must look convincing, so Pierre commands that Georgie share his bedroom. If he has to do this, he fully intends to enjoy the more pleasurable benefits, too...but soon he finds himself wanting to promote her from temporary mistress to billionaire's bride!"--p. [4] of cover.

Interesting to note:
Two diff books - same author
Same plot - same-named heroine
♡Bedded at the Billionaire's Convenience - Cathy Williams
(Pierre Newman & Georgie)
She is primary school teacher.
Goes to London to tell him they are dating b/c his mom is depressed. They spend the night (snow) at mom's
It is exactly the same story/plot as
♡Marriage Bargain with his Innocent - Cathy Williams
(Matias Silva & Georgie White)
She tells him b/c his flaky mom is depressed, that she told his mom they're dating.
He escalates it to engaged
She's a food photographer.
At some point she runs off to Paris

srsly - that can't be right, same author, both h named Georgie?
In both books his parents are on the flakey side?
Yup, just checked GoodReads,