Death Parade
It’s really good at making you invested in the two random people that show up and the conflict of the proper way to judge people.
Unfortunately, the side characters don’t have enough screen time to develop to the point of understanding their motivations, which damages the plot a bit. That being said, the way it gradually develops Decim to want to feel human emotions is really well done, Chiyuki’s judgement is extremely investing, and the the pilot episode is an amazing experience when no further context to reality is given.