Wow. What a chapter. That was a lot to take in too much for me to comment on all of it, but I'm very impressed. The dark theme was handled really well.
To me, the spanking works as a representation of the sort of abuse of authority levelled at underlings in black companies. It's the hallmark of a psychopath who's operating without any checks and balances in place. Seems to be a big problem in Japanese work culture The way she was worried about ruining her reputation by reporting what happened to the police shows the structural injustice really nicely.
Also, the faces might be a bit rough, but Sashimi is pretty damn good at drawing vehicles.