Hi Freaked, here are some affiliate programs with extreme or fetish content :
FETISH HITS : pregnant, clinic, spank sites and more
DERANGED DOLLARS : Sponsor Assylum and Patients revenged, slavemouth, extreme sites
SM Revenue : tons of extreme BSDM sites : rubber, smoking, hardcore bondage
FETISH WEALTH : horror porn movies, BSDM, exteme porn
Hope this helped