Seems like Grincher can corrupt save data. So, do not open any mail from Grincher, leave any room you see Grincher in, and do not join any room with a 1,000 player limit called "Grincher's Happy Room". This is not a joke.
Edit: Kicking Grincher from your game does not work, they are not affected by the kick action.
this sounds like a 2000s spooky rumour 0_0
not saying I don't believe it, but that's just what it reminds me of
Definitely possible, a similar thing happened in both DS3 and Elden Ring shortly after release IIRC. I'd imagine this is a troll who decided to target Webfishing explicitly because of the "straight" title drama.
It's really freaky to experience it in-game. They keep joining my games, and they can't be kicked, so they just sit there, menacingly. As soon as I found out they could corrupt save data I just started leaving whenever they joined. It may or may not be true but I don't want to risk it.
Back up your save data since it's stored locally in
appdata%
(not a real operating system). Consider using git as well.