Everyone Is an Idiot but Me

It's rare to have someone like Izumi given more than the role of a secondary antagonist, let alone the MC. She's brash, arrogant, full of confidence that LEAPS between semi-earned and completely delusional. You wish you loved yourself half as much.
Look through the eyes of an incredibly judgemental, radioactive employee who assumes the worst about everyone she meets (unless they're a cute guy being mildly polite to her). She is awful - demeaning, malicious, the kind who can't stand to see anyone praised in her presence. You can't even call her two-faced - she'll call you a fat waste of space in front of and behind your back. She's tries to orchestrate the date rape of a coworker for stealing her shine! (luckily it doesn't pan out the way she wants)
Watch this tar pit build her demise while accidentally elevating others. Her coworkers allude to the fact that while she's walking around with her nose in the air, the very people she looks down on are manipulating her like a dog.
I also liked her hints of growth. Don't get me wrong, she's a villain from start to end - but the seeds of doubt have been sown. Is this the person she wants to be? But not consciously - Izumi becomes a *slightly* less scummy person fully against her wishes.

The biggest ??? was how she still had a job after she's caught doing something REALLY bad. I'm all for companies coaching their employees rather than firing them the second they mess up but uh. I don't think this level of job security exists