Basically, you play as Death. As the story goes, Death is the CEO of the afterlife, and his company's admins, known as sorrows, have pretty much taken over the company and have become scarily efficient at reaping souls, which leaves death with a lot of paperwork. Eventually, he suffers from burnout and needs to stop his employees in order for him to finally take a vacation.
That's all I know so far, as I have only really gotten past Brad and not much else.
According to the game itself, the game is a satire on work culture. It covers themes of harassment, burnout, su1c1de, and addiction. It warns players beforehand that the game can be sort of dark in this regard, and I can appreciate that.
I also like how one of the themes is that death's motives is to go on vacation so he can cure his burnout, but I strongly question the choice of making him the CEO, rather than one of many psychopomps. Plus, the blame is being placed on your employees for death's work troubles. However, the game points out that death isn't exactly a wholesome chungus 100 boss either, so I cannot really get too mad at it.
However, if you played through Hades and liked it, I think you'll probably like this game.