Witnesses say he then stormed out of the room with a gun, pistol-whipped both women, and raped one of them.
The man escaped with cash from the Redondo Beach Boulevard business.
The suspect is described as a having "Asian-shaped eyes".
He is about 20-years-old, stands five feet six inches tall, and weighs 200 to 220 pounds.
He had a shaved head and a clean shaven face. He was wearing a black and white t-shirt and black pants.
Anyone with information should call the Gardena Police Department at 310-217-9635.