There is a black hole in the center of almost every galaxy, and the Milky Way is no exception (Orsay raised a question about the black hole in the center of the Milky Way, with a mass of about 2 million solar masses).
Many astronomers suspect that the center of quasars is a black hole, and its mass may be hundreds of millions of solar masses.
There are many quasars, and every constellation will have quasars.