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Demonic Incubus is the Hell version of the incubus found in our world.
Demonic Incubi are usually formed after a Hell Demon or more finds a male human to mate with and have sex. They unleash their Hell and Demonic energy onto him which turns them into a Demonic incubus. Though most of the Demonic Incubi are usually fallen heroes as Hell Demons favor strength and so go after those with strength and power. However, the Hell Demons would still turn some non-combative male humans into Demonic Incubi like the mamanos as they do desire husbands who are good as well.
Demonic Incubi usually are seen in Hell as they feel somewhat comfortable in that location. Many Hell Demons seek the Demonic Incubi to be their husbands as they see them as strong and sexy in their eyes.
Compared to normal Incubi, their demonic counterparts still like to have sex, never get bored with having sex, and don't get weak with age or age in general. However, Demonic Incubi gain a slight mental change which makes them always like violence and torture especially when both are done with their Hell Demon wife(s). Like the female Hell Demons, Demonic Incubi usually go and rape the female damned souls in the Infernal Rape Pits.
Demonic Incubi's strength and power improve after becoming corrupted as one was known to be able to easily overpower 10 humans at once without even stopping. Alongside this power, Demonic Incubi are immortal as when they die they will always come back to Hell. The reason for this is due to Asmodeus having drunk the Hourai Elixir which made her a Hourai Immortal and due to her connection to all of the Demonic forces they all became immortal.
The most well-known Demonic Incubi among Hell's forces is Val, a Former Chosen Hero sent to go and take down the New Dark Lord, Asmodeus. However, he instead became a Demonic Incubus and became Asmodues's husband. The reason is due to Val finding out the truth that he was merely a tool and ended up joining her and became her husband. He helps lead Asmodeus
Asmodeus sees the Demonic Incubi as a chance to help out with reproducing Hell's Demons after many of them have been permanently destroyed after Davoth, Asmodeus' predecessor, was killed by the Doom Slayer, which meant that all Demons and Hell energy outside of Hell was destroyed. She also sees the Demonic Incubi as a way to help atone for the violence done by her predecessor in the past while also helping with achieving Davoth's original goal of immortality for his people.
A/n: Yes here we go a new type of incubus that shall be present in the FMGE!verse. It would make sense these guys would from due to the combined power of Hell and Demonic Energy.