Reminds me of /fucktsarevich, a sub only for hating a particularly arrogant and unpleasant character in Genshin Impact…
It’s more the quest that’s the problem than the NPC.
The NPC has a repeatable quest that has a random really low chance of being available on each IRL day. It will become unavailable again the next day regardless of if you do it or not and if you were successful or not.
The quest has three different paths. Doing each path successfully at least once gives you an achievement that’s prob the hardest to get in the game, because of how low the chance of it spawning on a given day and you logging on to the game and checking if it is available that day are. And it has to be repeated at least three times (more if you fail the quest).
The rewards are negligible but completionists get understandably pissed off.