Billy Kong, formerly known as Jonah Lee, is a ruthless hitman from Malibu, though he considers Taipei to be his second home, and is of Chinese descent. He is infamous in underground circles, and is known for getting the job done, no matter what. He first appears in The Lost Colony as one of the two men escorting Minerva Paradizo in Madrid, holding a pair of crutches - which later turned out to be a modified dart rifle to capture N°1.
In The Lost Colony, he is hired by the Paradizos to guard their estate during Minerva's experiment. He soon takes captive of Minerva and threatens her with her father and Juan Soto's lives, in his determination to kill all demons, as a result of a traumatic childhood memory, in which his older brother Eric was dating the girlfriend of a gang member, but lied to him, saying that his injuries was from fighting demons instead of the gang dispute. When Eric was finally killed, over the years Billy forced himself to believe that Eric had lied, resulting in his plummeting behavior. However, when Minerva successfully proved the existence of demons, Billy came to think that Eric had been right after all, and wanted revenge on the demons.
He later made a deal with Artemis and traded Minerva for N°1 at the Taipei 101, with the intention of strapping a bomb onto №1 and sending him back to Hybras to explode and kill most of the demons. Though his plan unraveled utterly, with both №1 and Minerva escaping his clutches, he followed the group as they attempted to revive the circle of demon warlocks, and one of his men managed to hook the bomb on to Holly; both Minerva and Kong were mistaken that Holly, like №1, was a demon.
Kong and all his men were later knocked out by Butler in the ensuing battle. After Artemis, Holly, N°1 and Qwan had left for Hybras, Butler recalled the information given by Foaly that Kong had been suspected of stabbing and killing a colleague earlier, and together with Minerva, under pseudonyms, turned him over to the investigating officers, saying Kong's men had called him "Jonah" and mentioned that he "haven't notched (his) barrels for a long time", which means he had not committed murder for a while. With his former name, the officers successfully retrieved Kong's criminal history.
Kong is described as being wiry, slight and concerned with his looks, as he usually carries a mirror with him everywhere. He also has time for grooming, even when preparing for, or in the middle of, a kidnapping. Kong's black hair is usually in spikes and is highlighted.
- "You need to understand a few things, Paradizo. First, you are not in charge here. Not really. Not since my men and I joined your little group. Secondly, I don't generally work on this side of the law. My specialty is taking whatever I want by any means necessary. I only signed on for babysitting duty because I owe these demons a little payback. A lot of payback, actually. I know little Minerva just wanted to take photos of her guests and ask them a lot of psych questions, but I have my own plan for them. Something a little more painful."
- ―The Lost Colony [src]
- "So, you must be the great Artemis Fowl. Minerva's idol. I am so sick of you smart kids. Why can't you just boost cars or steal stuff like normal kids? -Kong
"We do steal stuff. Just bigger stuff." -Artemis"
- "Born Jonah Lee, Malibu, early seventies. Family originally from Taiwan. Mother, Annie. One older brother, Eric, killed in a gang fight. The mother moved them both back to Hsin-chu, south of Taipei. Kong moved to the city and became a petty thief. He had to leave in the nineties when a row with an accomplice turned into a murder charge. Kong used a kitchen knife on his friend. There's still a warrant out for him there, under the name Jonah Lee. Moved to Paris and changed his name. Took up martial arts. He's had a facial surgery, but not enough to escape my computer."
- ―Foaly [src]