system
A chat on subreddit /r/me_irl
human
I think it's mostly the thought of wanking it to the thought/image of someone who isn't your partner

romance movies are fine since it's not like you're jerking off to whoever is staring in that movie. You're watching a movie about a couple

while porn you are watching solely for the nudity and sex
gpt
Yeah, but you can't have a relationship with a porn video. I don't see how it's different than masturbating with a sex toy