The wonderful starlets Becky Sharpe and Orita De Chadwick make PLEDGE SISTERS watchable. It's a porn quickie resuscitated on Vol. 119 of Something Weird's Dragon Art Theatre series.
They play actual sisters, with elder Orita trying to get younger Becky to join her Kappa Delta sorority. We see them wandering around a campus but there's no schooling in this film.
Rather, it is bookended with sorority rituals, cheaply staged with a goon getting a blow job as each of the lead actresses lies spread-eagled in bondage on a makeshift altar.
In between these two scenes is porn action wherein Orita tries (and succeeds) to corrupt little sis. While she makes out with her blond boyfriend she gets Becky to make love to his roommate, the inevitable Ric Lutze, clad in one of his goofy jumpsuits. There's not much else in the way of plot. A supposed incest angle when Orita (masked) applies a dildo to Becky comes off as the usual porn content, with zero impact.
Theme is rather cynical about the "new morality", with Becky joining in but by the time THE END appears on a card inside a textbook, she has renounced the free-sex approach to instead better herself as a person by concentrating on getting a good education. I daresay the anonymous pornographer who made this film is beyond tongue-in-cheek here, though for all I know he could be an underachieving Rhodes scholar like horror maestro Wes Craven.
Musical track is extremely unusual for porn, emphasizing Gregorian chants (during the ritual scenes), throwing in the Hallelujah Chorus, Bach's Toccata and Fugue in D Minor and Thus Sprach Zarathustra while employing both free jazz and musique concrete during the sex scenes. A version of Donovan's "Sunshine Superman" plays at the opposite end of the musical spectrum.
For the uninitiated, Sharpe is a true porn beauty, who seems like Ally Sheedy as styled in this particular movie. Orita always delivers the sexual goods. The underage looking stud who appeared opposite Becky in JEANIE'S MAGIC BOX also puts in an appearance.