This one is super unfortunate, because Booth has a strong, fun voice and can write a hot scene...but a strong voice couldn't overcome the absolute lack of tension and conflict, so it ended up feeling about 100 pages too long.
So here's the setup: Billionaire hero goes Undercover Boss as a delivery driver. That's a concept that promises all kinds of awesome conflict. There are secrets! What happens when she discovers the truth? Will she feel betrayed, hurt? What obstacles will lie in the path of their happy ending?
The answer is ... nothing happens.
Remember those plot charts from literature class that show the rising tension created by internal and external conflict? The key, of course, is RISING -- and the chart for this book is flat.
He's a billionaire undercover. She finds out before he tells her and is perfectly fine with it. Accepts it easily.
And that's all that happens. But the story goes on for another one hundred pages as the heroine and hero continue to have sex and move in together and go to a gala and have hot sex...
Never once dealing with any tension at all. Never arguing. Never having any significant conflict come up between them or in their outside lives (except some easily solved work conflicts.) Nothing to keep them apart. I kept waiting for something to happen. I kept waiting for the book to end because I wasn't sure why it continued. She'd found out about his real identity, and he was great, and she was a little uncertain but overall fine with everything, a real trooper.
So there was no character arc. They never had to overcome anything so they never had to grow emotionally. They just easily fell in love and had hot sex and there was absolutely no reason to make him a secret billionaire because that conflict never mattered. They didn't have to fight for anything. There were no stakes, no threat of losing anything.
Which all adds up to no conflict, no tension ... no plot.
A pity. The actual prose is good enough that this story could have been great. Instead it's a lot of nothing.