A college girl named Leah befriends a fellow student named Pearl and falls in love with her much to the dismay of her mother Julie. Leah learns that Pearl is a Nightwalker, needing to kill people to consume their blood. Pearl belongs to a gang of female Nightwalkers that preys on abusive men and forcibly inducts women into their group by biting and then not eating them. The Nightwalker Queen has her sights set on Leah as the next member and wants Pearl to bite her, threatening to bite her herself if Pearl doesn't comply. There is a sexual component to biting, as is discussed in a thematic English class' discussion of vampire novels Dracula and Twilight, characterizing the threat as one of rape. Julie tries to get Leah interested in dating a man, Bob, who she knows to be attracted to Leah. Bob feels entitled to Leah as a long-time friend and is upset when Leah indicates contrary interest in women as a lesbian. He conspires with Julie to expose Pearl as a bad person to win Leah's heart. When this is ineffective, he spikes her drink with a date rape drug and attempts to rape her. The Nightwalkers attack him and start to eat him but are interrupted, allowing him to transform into a Nightwalker. Now given enhanced abilities, Bob leads the Nightwalkers in an assault of Leah. Julie is killed trying to rescue her, and Leah takes vengeance by bludgeoning him to apparent death. Pearl apparently kills the other Nightwalkers and bites Leah on her request so that they can live forever as a romantic pairing. In an epilogue sequence, we see the heavily-scarred Nightwalker gang still active, now influenced by Bob to attack women without reservation.
Critical reception for Mother, May I Sleep with Danger? has been mixed and the film currently holds a rating of 56% on Rotten Tomatoes, with an average rating of 5.4/10, based on 9 reviews. Sam Adams of Rolling Stone wrote a mostly favorable review, commenting that the film was "junk that knows it's junk" and that its "great feat is that it's a movie that manages to be both exploitative and progressive, in the way that Russ Meyer's movies feature strong female role models and also provide ample opportunity to peer down the front of busty young women's blouses." Daniel Fienberg of The Hollywood Reporter wrote that the film took itself too seriously in its first portion but that its third act "kicks into gear".
