I just can't find this quest with any search engine.

In the quest you meet a trapped man who his friends and is plagued by hunger.
The only edible thing in the area are some fish and a voice in his head tells him to eat the fish, but something doesn't feel right.
So he turns to you for advice, I told him it's probably nothing and he should eat the fish.
Later on it is revealed that something turned his friends into the fish for fun to see if the man would really eat them.
I think the mans story ended with suicide out of guilt.

I first thought it could be a quest out of the Elder Scrolls universe, because this scenario seems like a something a daedric prince would do, but I can't find any information about the quest anywhere.
Does anyone have an idea from which game this quest comes?