Demons (悪魔?) are a key feature of the Megami Tensei franchise.
In the Megami Tensei franchise, "demon" refers to any supernatural entity that can bring harm to human beings or interfere with their lives in one way or another. This includes more conventional malevolent demons, folktale creatures, deities, and Judeo-Christian angels.
A staple gameplay feature of the series is the ability to negotiate with and/or recruit demons as allies and party members, usually through the use of a COMP with the Demon Summoning Program installed; many demons will request Items or Macca in exchange for their services. In some games, summoned demons often require Magnetite in order to maintain their corporeal forms; without a constant supply they will lose HP with each step.