The whole point of fiction is that there is no "line", that you are pretty much free to explore whatever the heck you want, be that nuking an entire city of innocents or playing as a 1 year old child prostitute soldier robot who has to torch adorable space bunnies with a flame thrower.
If I want "lines", I'll go with real life thank you very much.
If I want "lines", I'll go with real life thank you very much.