An Incubus is a demon in male form supposed to lie upon sleeping women in order to have sexual intercourse with them, according to a number of mythological and legendary traditions. Its female counterpart is the Succubus. An incubus may pursue sexual relations with a woman in order to father a child, as in the legend of Merlin.
Religious tradition holds that repeated intercourse with an incubus or succubus may result in the deterioration of health or even death. In medieval times, the church would use incubi and succubi to explain sexual functions, which were taboo subjects.
"Origin: Germany. A male dream demon. It enters women's dreams to have sex with them there. They are said to take men's semen from Succubi to impregnate women."
—Shin Megami Tensei A-Mode DDS Dictionary
Shin Megami Tensei IMAGINE
Incubus appear in Ichigaya and Ikebukuro at night. They appear as support for the Succubus field boss in Shinjuku Babel's docks area and as field bosses within Suginami's Diaspora instance. Incubus appears as the final boss in the Deranged Scheme questline, as an apex in his attempts to seduce a Pixie.
Shin Megami Tensei IV
Two Incubi will be summoned by the Terminal Guardian of Ikebukuro, alongside a Kaiwan. After defeating the demons, Flynn and his fellow Samurai gain free access to the Terminal. Incubus later appears in Shibuya. It can teach Flynn the Zanma and Dream Needle skills through its Demon Whisper. Incubus can evolve into Succubus upon reaching level 37.
Incubus is also one of the demons summoned by Fusou Fujio in the second round of the "Hunter Tournament Finals" Challenge Quest.
Shin Megami Tensei IV Apocalypse
"Originating in European folklore, the incubus is the male counterpart to the succubus. It ravishes women while they sleep, impregnating them and causing nightmares."
—Shin Megami Tensei IV Apocalypse compendium
Incubus is encountered within Shinjuku in the west entrance passage, west entrance, west entrance buildings and government office plaza areas. He can teach the Marin Karin, Dream Needle and Zanma skills through Demon Whisper. Incubus benefits from learning ailment and Force skills.
Devil Summoner: Soul Hackers
"Originating in European folklore, the incubus is the male counterpart to the succubus. It ravishes women while they sleep, impregnating them and causing nightmares. Offspring born from such encounters are said to be evil spirits and witches. If one is possessed by an incubus, churches could perform purifications which could ward the incubus off."
—Devil Summoner: Soul Hackers compendium
Devil Summoner: Raidou Kuzunoha vs the Soulless Army
"A demon originating in European folklore, the incubus is the male counterpart to the succubus. It ravishes women while they sleep, impregnating them and causing nightmares."
—Devil Summoner Devil Chart
Persona 4
"A male demon of European lore in medieval times. They visit sleeping women and have sexual intercourse with them; the resulting children become witches and wizards."
Incubus appears in the third scripted battle of the game and is titled the "Bedside Brute."
The Shadow of Mr. Magario will take the form of Incubus during the request "Daughter's Just a Meal Ticket." He will lack a weakness to Gun and Bless skills in this fight. He will attack normally with Dream Needle, however should any party member be put to sleep from this or by Shadow Mrs. Magario's Lullaby skill, Shadow Mr. Magario will follow up by targeting party members who are asleep with the One-shot Kill Gun skill.
DemiKids Light & Dark
"A mischievous demon who feeds on the fear generated by nightmares."
Known as Inkubus, he can perform the combo Spark Bolt with Succubus. Inkubus also has the power Vixen Allure.
Shin Megami Tensei: Liberation Dx2
"Originating in European folklore, the Incubus is the male counterpart to the Succubus. It ravishes women in their dreams, impregnating them. The children between an Incubus and a human become demons or similar ilk."