I'm not sure exactly as I haven't read it. But it might be about a character facing a sudden and extreme situation, like being thrown into the 'deep end' which could symbolize a difficult or challenging new environment or set of circumstances.
I'm sorry, I don't know who the author of 'falling into the deep end novel' is. There are so many novels out there, and without more information, it's hard to determine the author.
A falling cohabitation manhwa on Toonkor attracts because it offers a fresh take on romance and cohabitation. The drama and tension keep you coming back for more. Plus, the world-building is immersive.
Most likely, it's not a true story. It could be inspired by various elements but not based on real events. The plot and characters are likely crafted by the author's imagination.