Brutal serial rapist who made victims call him ‘master’ loses bid to get out of prison before age 103 Updated 2:27 PM; Today 2:27 PM Facebook Share A brutal serial rapist who treated his victims as sex slaves and ordered them to call him “master” will keep serving a 78-year to life prison term after a state appeals court Thursday denied his appeal. Seth Mull, 33, had no luck convincing the Superior Court panel that he should have been tried separately in each of four cases where he was accused of raping the women and sometimes binding them and forcing them to have sex with other men as well.