OK, this begs the question: If the grim reaper can age up, does that mean he can also die? And if so, who collects his soul? :-)
This
is the question.
You used to be able to invite the Grimmy into your household using cheats and what not...however this was causing serious issues. Grim is sort of a service sim, and like any other service sim who joins your household, there was apparently nobody creepy enough to fill his position. So when people died,
nobody came to collect them. They'd stand there as ghosts forever, and the people who witnessed their death would be stuck there in shock.
Another issue with Grimmy as an active sim is that he has no skin tone. Thus, if he reproduces, his progeny has a chance of not having a skin tone. This has a tendency of causing severe graphical issues and corrupted sims. Thus, instead of just making it so he was replaced if he was cheated into a household, they just made it so that there was no way to get him.
Likewise, as far as I can tell, Mr. Reaper doesn't age normally.
This has lead me to a theory on this...one i have no guts to test. If you should age up the Grim Reaper to the point to where he dies of old age, you may be faced with the issue I described above.