She works at his company?

I forgot the book I read but basically in it the MFC worked at the MMCs company as his assistant and he genuinely never noticed her, until she slammed her two week notice on his desk. Then he becomes obsessed and starts stalking and sleeping under her bed, touching her while she sleeps. I don’t think I finished the book tho so I can’t tell you how it ends, but I read enough that I know I want more like it.

She doesn’t have to be his assistant but I want him to own the company and not notice her until a certain moment happens.