Behind the Greek Door (1975)

Gary is pledging to the Chi-Alpha-Chi fraternity and six guys hold his future in their hands. They decide to give him a try. If he manages to pass their stiff initiation. But Gary's already up for it and is having vivid fantasies about the frat president. On initiation night, two members go off to the bedroom for a sensuous romp with baby oil and Gary is finally led through the Greek door.