Lips Manlis is a crime boss and Big Boy's mentor in the Dick Tracy comic books.
Lips Manlis appears very briefly in the movie. He is at the Club Ritz eating clams with Breathless Mahoney, who is very grossed out by his eating habit. Then, an associate of Lips comes forward telling him some guests have arrived at the entrance of the building. It turns out to be a ploy, as Flattop Jones and Itchy hold him and Breathless hostage.
They take them to the warehouse, where Big Boy Caprice awaits him. His reasoning for being there is to force Lips to sign the deed to the Club Ritz over to him, while Big Boy's henchmen give him "the bath", which is a form of execution. Even pleading with Big Boy that they're pals, Big Boy claims there are no pals in this business, something Lips taught him.
Lips Manlis is covered in cement and sent to the bottom of the river, while Breathless becomes Big Boy's moll. Dick Tracy immediately launches an investigation and even though he finds Big Boy's nuts at the crime scene, is unable to prosecute him and those involved, leaving him a free man walking away with murder.