Paranor KYD: 9 Immortals
An excruciatingly attractive incubus, Tyrael serves as Guardian of New Myris. All tieflings are decendents of Tyrael. Tyrael was once the commander of The Devil King’s armies. However, durnig the invasion, he fell in love with one of the gods he was sent to destroy – Alina, She Who Does Not Judge. Eventually, The Star Beast destroyed Tyrael’s love, and the incubus disappeared into obscurity for several years. He reappeared during a decisive battle at New Myris between the armies of Beazel and the Booktenders. None of the Devil King’s lieutenants could match the might of the incubus, and were forced to retreat. He strode through the gates of the Great Library, wrapped in the shawl of his dead love, and swore allegiance to the city.
Now, Tyrael is sequestered in a private corner of the city where no women are allowed to enter. He emerges only to defend the city. Despite the self-imposed prohibition, Tyrael fathered several hundred children, who themselves reproduced prolifically, forming the tiefling race.