When a good person turns into a tyrant due to circumstances.
A fisherman catches a strange fish. At home, it turns out that the fish grants wishes. There are only three wishes, and only the fisherman's wife can make them.
A group of guys put on virtual reality glasses to play a shooter, but find themselves in a place indistinguishable from reality.
He fights fighters who use their signature move, but refuses to use it first. She doesn't engage in combat at all—until he's defeated. And then one day she'll have to defend herself.