Professor Jonathan Utonium is the unmarried resident scientist of Townsville and also the creator/father of the Powerpuff Girls. He created them while trying to make the perfect little girls using sugar, spice, and everything nice, until Mojo Jojo, formerly 's monkey lab assistant named Jojo, caused him to add Chemical X, thus creating the Powerpuff Girls, while accidentally turning Jojo into his future villain self, Mojo Jojo. The Professor loves his girls very much and sometimes worries excessively about them. It is mentioned that he is a bit of a father figure to Dexter as well.
In FusionFall, he is found at Genius Grove, alongside Dee Dee and Numbuh Five by Dexter's old home in the past. Also please note the professor is nowhere to be found in the Future. Because Buttercup is his daughter, he is very sorrowful about nearly losing her after her last fight with Mojo before Fuse's arrival, but will be very happy when the player tells about what happened to her during the "I'm Still Standing" mission given by Buttercup at Marquee Row. He has a strong love and always makes sure his girls are all right (leading him to falsely identify Fusion Bubbles as the real Bubbles in a clouded battlefield). His Fusion is named Professor Plutonium and looks like an exact duplicate, except with a lab coat and tentacles coming out of his back. He is the only Fusion that has a name that doesn't begin with "Fusion." This has been changed so his name is now "Fusion Utonium."
In the manga, the professor seems unaware of Computress's secret crush on him as they deal with the Terrafuser. His Fusion counterpart, Professor Plutonium, has tendrils and is fought in the same Infected zone at the same level.