I can identify several different fetishes in this thread.
One is the simple sadism fantasy as in torture or whipping drawings.
Another is the "ruined orgasm" fetish, where someone is enjoying himself and orgasm is inevitable, only to be ruined by unexpected shocking pain.
Yet another seems to be "masochist creation" where someone is in a painful situation that results in a powerful orgasm, changing his sex life forever.
Myself, I enjoy fantasy alternating pain and pleasure where the victim is overwhelmed and doesn't know if she likes it or not.