The Grim Reaper in The Sims — the original 2000 game — has a hidden personality score that is accessible in the game’s data files but never displayed. His personality traits, if examined, show maximum Neat, minimum Nice, maximum Serious, and average scores in all other traits. He has no friends, no job, and no wants panel — but he does have a hunger bar that depletes normally.
If, through cheat codes and save file manipulation, you place the Grim Reaper in a household, he functions as a normal Sim with specific restrictions: he will not age, will not die, and will not build relationships beyond acquaintance level. He cooks, he sleeps, he watches television. His cooking skill caps at three regardless of practice.
Players who have explored these hidden personality values have interpreted them as Maxis worldbuilding: the Grim Reaper is tidy, humourless, efficient, and incapable of genuine connection. His in-game design is functional rather than characterful. Maxis gave him the personality of his function.
The Grim Reaper’s hunger bar, specifically, has never been officially explained. He has no storyline that requires eating. The hunger bar exists in the data and depletes in normal time, suggesting Maxis built the Reaper with full Sim functionality and then removed all content reasons to engage with it.

Currently on my first run and now I have to go back and look for this. Worth the detour.
Found this by accident on my third run. Came here to understand what I was actually looking at. Great write-up.