Is GAF avoidable?
It depends what you mean by "NTR focused". The threat of NTR is the key source of conflict that drives the story, but the actual NTR content is avoidable, and it's a small percentage of the overall game.
Poor analogy but think of it like player character death animations in a survival horror videogame. 
Dying is not the focus of 
those games, and yet those death scenes are gruesome and detailed. If you don't want to see them, don't die. But there are some people who like to watch them for whatever reason, be it morbid curiosity, twisted sense of humor, etc.