The Love Monsters are nymphs,that are female nature spirits from the Greek mythology.They are fairy versions
of the female students in the Torrington Academy,that became Love Monsters because of the Cursed Guitar in the episode Curse of the Six-String Serenade.The Love Monsters are desesperatly in love for Martin,as the Cursed Guitar make everyone fell in love for who plays it.However,they get back to normal in the end of the episode when Matin plays his song backwards on Torrington's PA syestem.