Relationships, and the tragedy of loss and misunderstanding inherent within them, are major themes in "Boogiepop Phantom". The relationships that the characters Mamoru, Manaka, and Shizue have with their parents highlights the lack of support that children receive from parents who are otherwise busy, and the resulting disconnection between parents and children. With the actions of Poom Poom later in the series the theme of the Pied Piper is explored, as Poom Poom takes away the children because the parents have broken their promise. The message the show leaves the viewer however is positive, as both Manaka and Shizue reconcile with their mothers, and so the parent-child relationship can be saved by open communication and understanding. Another form of relationship is explored through the interaction between Moto and Manticore Phantom, where the physical surrender of Moto, who harbored feelings for Masami, associates the sexual relationship with death.