A fired Northwestern University professor and an Oxford University staffer accused of killing a 26-year-old hair stylist last month were acting out a sexual fantasy when they allegedly stabbed the victim dozens of times, prosecutors said Sunday. Wyndham Lathem, a microbiologist who taught at Northwestern University, and Andrew Warren, a financial officer at Oxford University, appeared in court Sunday for the first time since a nationwide manhunt for them ended earlier this month. Prosecutors said Lathem and Warren had chatted online for months about their shared fantasies of murdering people before Lathem flew Warren to Chicago so the two could bring their ideas to life. Lathem is then accused of “luring” his boyfriend, Trenton Cornell-Duranleau, to his apartment and asking Warren to film the scene as he allegedly stabbed the man repeatedly while he was sleeping. The two have been held without bail after a judge denied their request for bond. Lathem was fired from the university earlier this month after fleeing when a warrant was announced for his arrest, and Warren has reportedly been suspended from his job in Britain.