I do not understand how the grit system works, I have enabled sex defeat and I fight them until they are almost dead and then let them "deafeat me" but they just kill me :'D
You need an equal amount of grit points as the enemy has difficulty points (grit points = fist icon top left, difficulty points = skulls above enemies).
but how to increase the grit points? and a minor tip in your log/tutorial you say you need to sleep but dont say how to sleep. just mention the key binding letter there too. :P