Enables allatostatin receptor activity and neuropeptide receptor activity. Involved in neuropeptide signaling pathway. Located in plasma membrane. Is expressed in adult brain; adult mushroom body; larval VUM motor neurons; neurosecretory neurons; and ventral midline of embryo. Orthologous to human BRS3 (bombesin receptor subtype 3); GRPR (gastrin releasing peptide receptor); and NMBR (neuromedin B receptor).